Hi,
first LS, ancient race: necrontyr or Eldar... make your pick

Custodian: approved; labelling it as a Grand Cruiser at the expense of 2 missiles would make it excellent

Warden: @LS, the Warden has swivel ion cannon, orca swivel battery. Is worth something. Warden also pays for looking cool.

approved.
Protector Lar'shi'vre vior'la: YES! Moving launch bays to the abstract dorsal (they are keel) is an idea.
(eg even Distant Darkness has no 45cm Ion Cannon on the Protector).
Protector Lar'shi'vre tol'ku: ? Make it 90*, all railguns fixed forward and missiles to str4.
Emissary Il'porui, give'em all 90*. all firepower fixed forward. Drop missiles to 3. Out of principle I would always take the 90* variant if the others don't change.

Castellan, approved. Perhaps a 5cm boost?
Orbital City/Orbital: approved (under the current defences overall seen),
Fleet list: Yes.
Overall: iron out the variant options for Protectors and Emissaries with 90* turn rates and consider it done.
Same as for Marines, make official with above changes and a revision in two years.