Assuming that the Bug Invasion is over and the next WC deals with some other threat.
By 2690, Confed should have all 10 planned Midway Class built and launched. Older Concordia Class will probably have been retired by this time (considering that Confed vessels seem to only have at most a 20 year service life, and any war-era ships will be vastly outclassed by any post war-era ships anyway).
Vesuvius Class ships will no longer be constructed simply because they are too expensive. The remaining ones (however many that is...but for arguments sake lets say 5) will also be in service.
That gives Confed 15 Fleet Carriers...(more than they had at some low points in the war).
Now, without any real known threat to the Confederation, the money people will not (no matter what the military want) pay for anymore fleet/super/mega class carrier vessels. To bloody expensive and not needed.
IMO if we are not serving on the Midway again, the next class of carriers that we will see in the game will be based on the Hades style. Fast, well armed but with small numbers of fighters (imagine the Tarawa being a purpose built carrier and not a hastily converted Transport).
Big carriers are nice and dandy for a show of force, but everyone always goes and attacks the big carriers first! I would rather be on a smaller ship...at least there is a chance it will still be there at the end of a battle!