I typically have two fleets, one with the hightech battelship (forgot the name) and 8 apogees, no other carriers.
Other fleet depends on parent faction, but typically 5-6 battleships and only 1-2 carriers. I don't typically go for light/medium carriers in late game.
What I should probably do is only make actual carrier bays count for the threshold and ignore warship bays altogether for the threshold calculation. Your fleet description sounds like it would greatly surpass the threshold and drop the bonus to very little unless running a destroyer/frigate fleet.
So if I leave it at, say 25, and ignore warship bays, then that would account for 2 capital carriers
with Converted Hangar installed or roughly 4-5 cruiser carriers at the full bonus. You could also fill in your fleet with half of the fleet consisting of light carriers and probably not surpass the threshold. Or of course you could use something like 1 Astral, 2 Heron, 1 Condor and 1 Vigilance for 25 total carrier bays.
Of course, warships wouldn't actually get the bonus either. I'll look into how hard that would be to do. I'll probably have to play around with the numbers to see what feels the best.