Wrong comparison. Try it against a Repulsive and see what you get. 
- Nate
OK, so it has an identical profile to an extra-shield Repulsive with 2 minor changes. It has 3 prow lances instead of torps. This is equal value. It counts as a BB for turning rather than a cruiser, so has a larger turning circle and can't use CTNH. It's 5 pts more expensive. So far I'd say it's a little pricey given the manoeuvrability issue.
Super batteries - slight issue with this is it describes them as granting long range accuracy (represented by no column shift) but then also counts as always closing when at normal range.
Disengages when crippled - sucky downside from a play sense, though it's logical enough, just like the Demiurg. The fact that it gets +1 Ld for disengaging is actually a downside from a play perspective, though not so from the Fra'al's point of view.
Hard to tell but the downsides may just equalise the upsides here. Still a bit pricey given that the Rep can get an extra 15cm range on the dorsal lances and is more manoeuvrable. Still, more balanced than a Bastion.
From a background perspective I quite liked the old "Fra'al are big bad monsters" concept where you can't get them as allies, but just as an enigma that act unpredictably. They come in, kick some random peoples arses and piss off again. Also liked their special weapon, though it did need some tweaking.
Regarding their fleet inclusion, it's nice to see some non-Demiurg xenos cap ships.
Hi Sigoroth! Thanks for the feedback! Try playing with two of them as a pair, exactly as you described- they ally with nobody but play nice (ish) with pirates. This is a FUN ship I have been trying for YEARS to see made part of the game as a scenario gimmick rather than anything actually fleet-worthy.
Here's why this proposal gets rid of the Ether Cannon- KISS. The Fra'al ships are not supposed to be as good as Imperials. If they had some kick-@$$ weapon that could beat on the Imps, they would either be a much bigger force in the galaxy than they are like the Dark Eldar, or the Imps would have mustered a crusade to exterminate them like they did to a number of minor races that got too uppity like the Yu'vath.
Who's the Yu'vath? Exactly.
Really, all of us are trying to steer away from unusual game mechanics, which the game is already replete with. By using entirely ordinary game mechanics, I took a ship profile that already exists and is well-tested, swapped out the prow weapon with another that is already tested as being an equitable trade, turned it into a "battleship but smaller" and play-tested it. What you see is the result. I see the better guns as a xenos technology unique to the Fra'al that Rogue Traders can graft to their ships as a refit, or Chaos duplicated (though imperfectly) for their Idolators.
Now for a peek behind the veil. Che Webster's Fra'al battlecruiser was such a good idea, a model was actually made for it, but for reasons beyind this post that model became something completely different: the Demiurg Stronghold. Incidentally, some of its special rules were incorporated into both the Demiurg, and to a lesser extent, the Necrons.
- Nate