TL/DR. 
BI, you really need to understand that the community is not against new ships or content. They are against things that don't fit the feel of the existing fleets. As the HA have stated before and probably will again, not to mention the admiral and Sig, there are certain themes that the various fleets were built around and that determine the type of ships we place in them. Some ships, like the Jovian, violate those themes for one reason or another and require special treatment (in this case, the jovian is only allowed by reserve in Bakka and can't be used in any other IN fleet list) so they don't alter the fleets from their intended function.
For IN that means you shouldn't be making a 25cm battleship with 90` turns or dedicated carriers as the core of your list. If you want to do that, you need plausible reasoning for the ship as well as plausible capability to create such a vessel. In the former example, the Imperium is declining in technical knowhow and such things are beyond their capabilities to produce. In the latter, it's been stated over and over that the IN mindset is that of a big gun fleet rather than a carrier fleet. This isn't to say they aren't capable of producing dedicated carriers or haven't experimented with them, just they would rather bigger guns than more bombers and thus a craft that forgoes nearly all gunnery for carrier capability should be decidedly rare as with the Jovian.
*sigh*
Ok, I'm gonna take a deep breath here and make a point I think that you all might grasp. The 'feel' of a fleet, particularly one that is as flexible as IN, differs from person to person, based on the style of fleet that particular player tends to build. Thus, from my perspective, IN is more akin to WWII then WWI. In this, there are big guns, they have their role, but carriers have a key role to play as well. The idea of a 'pure' carrier would be unusual, but not inconceivable in this scenario, particularly considering how close the number one most common battleship in the Imperium, the Emperor class, is to being a pure carrier. From what I've read in fluff and with the newer offerings from FFG, there is the direction that the fluff, at least for the sectors of the galaxy around the eye of terror are heading with such local ships as the Tempest, which would not logically exist if the drives was simply toward bigger guns, as the idea of a purpose build escort carrier (as opposed to modified cargo ships) would be anathema to an 'all big guns' mindset.
The simple reason for this tendency may be the need to counter the large number of carriers that the ruinous powers seem to possess, particularly as, at least in fluff, there are capitol class 'pure carriers' in that region who's slow extinction would be a strong motivator for a stopgap such as modifying a Mars into a Jovian.
In the areas outside the tendency toward big guns as symbolic of Imperial Authority could, in theory, continue unabated, as they are quite effective against orks, etc. This is why the arrival of the Tyranids has been so difficult for the Imperium to stop, navally, as AC are quite effective against them, but millenia of fallout from the Gareox Incident (which is none too clear now that Bakka was not part of the Imperium at that time) has left the 'southern' segmentums vulnerable.
As far as technology goes: While the command and control functions of a carrier are more advanced then other ships, the simple fact is that they're actually much simpler to operate and maintain then a 'big gun' battleship. If the Imperium's technological base was truly in the sort of downslide that is indicated, the relative simplicity of a carrier to maintain and operate would make it more attractive, not less, considering that anything with a spaceworthy hull can be made into a carrier. (See escort carriers)
Nope, range is definitely related to power. However, if you have crap accuracy your effective range could drop. IJN battleships had bigger guns than their American counterparts for the most part, but the yanks did better because of more accurate radar. Improving yank accuracy would do little to improve their range, whereas improving Jap accuracy would. They had the more powerful guns, so better potential range.
Apart from notions of how one would justify the IN already having powerful enough weaponry to shoot far but just crappy electronics (easiest thing to upgrade), it still doesn't fly here. Because to get accuracy on this scale you would need to have power regardless of how top notch your electronics are. To be shooting at a bomber in the middle of its attack runs while it's avoiding defensive flak and possibly about to go into the friendly's shadow you would have to be talking in the seconds for your shot to arrive, not minutes. That means that at a maximum of 15,000 kms we're talking roughly the 1.3% C that BI brought up in his ME2 quote. That's a hell of a lot of power, and it's going to damage whatever it hits, even if it's just some frozen peas into metres thick armour.
Except in space, range is not reflective of power at all, power dictates relative velocity instead. To hit even the largest ships at the ranges involved would require accurate targeting, as it would be impossible to generate enough fire to 'cloud' a target through volume of fire at these ranges. (This is why the gunnery table is a lie. The targeting cogitator on any given ship would either hit or miss, as they would all be tied to the same sensor data and motion prediction. At the ranges represented, human fire control would be far too inaccurate to even come close to a target. How orks and necrons do it, I have no idea, though I suspect they're both very different. Eldar can see the future, so motion prediction is no problem. Tau get around it through advanced sensors and self guided missiles, as well as the railguns projectiles moving at a significant fraction of C.)
I would suggest that the FDT is a rapid cycling laser system with advanced motion prediction. The ToT at 15,000 km would be within parameters.
And again, your penchant for being obtuse misses the point again. I definitely get what you want to happen. However, I do not think another IN list is the way to go about it.
I am not saying change should not be incorporated. I am saying there are other races out there other than IN which need more lists than IN RIGHT NOW.
Yes. Grow. Grow the other races. Add more ships to their lineup. Add more unique (but not broken) rules. At this point in time, IN is already well developed without having to add another list in there. Unlike Dark Eldar or Necron or Nids. These other races need to be brought up in their fleet list varieties. That is what is needed to grow this game. Not another IN fleet list which in and of itself is conflicted. It wants a list with minimal ordnance and yet has access to ships which have the most LBs. That's one of the dumbest things I have ever heard.
IN has 3 lists already, 4 if you include the AM. Inquisition is coming up next. Compare this to 2 for Chaos, 2 for Orks, 2 for Eldar, 2 (technically) for Tau, 1 for SM, 1 for DE, 1 for Nids, 1 for Necron. The sheer number of variety in both ships and fleet lists for IN compared to the other races is already far ahead compared to the other races that I do not think another one is beneficial for the game.
The new IN ships are ok. But does IN REALLY REALLY REALLY need them? Answer me that in the affirmative. Prove to me that IN needs this change in order to help the game "grow". Does it really? All I see is it helps IN grow. But what about the others? I could create two or three more IN lists each with their own flavor and own ship designs but heck I would rather grow the other races first.
This coming from an IN player.
Actually there's 3 lists for SM now (have not seen new ones in IA 10), 4 for IN, 3 for orks (counting clanz lists as 1), 2 for eldar, 2(3?) for tau, 1 for DE, 1 for nids, 1 for necrons.
Lists that need new/more ships by order of priority:
DE (no brainer, need both ships and lists, possibly cabal fleets???)
Eldar
Orks
Tau
Nids would be better to get more biomorphs then whoile new ships, as they're more or less swiss army knife ships. Maybe specialized one for certain fleets? Levianthan, etc.
Necrons... necrons don't have a lot of variety in any list in any system. The fact that they, unlike everyone else, really are almost absolutely uniform means there would not be a lot of variation in their ships either.
Personal opinion:
As I said before, I would see them release a new list with at least three new ships in it per year for each race. It's not likely to happen though.
GW laid out rules, and, I hate to say it, IN, SM, Tau, Orks and Chaos are what they're pushing and they all have to be made with existing kits. This is the stumbling block. IN we can make new ships easily, as all the possible combinations of the original kit are not used, so I don't blaim the HA for using IN, which will probably be one of their easier sells, to try and load up new ships. A lot of IN ships were cut not, as some people have suggested, due to lack of quality, but due to the fact that content was cut to tidy up production costs.
This is due to most books being printed in groups of pages who's name escapes me at the moment. Printers will charge based on how many of these groups there are. If a group is 15 pages, and the text is 16 pages, it's more cost effective for the publisher to cut one page then to try and fill the remaining pages. (for those that are cynical like me, GW's actual cost per book for Armada would have been between 5-10 dollars per copy at the time they made it, based on an old price guide I have laying around.)
Jovian being published right away after bluebook makes it look to me like something that got cut for space by GW rather then something the designers decided to toss. In BB, each IN ship is more or less mirrored by a chaos equivalent, with a few exceptions. The exceptions were more then likely cut content to reduce printing costs.