This seemed like a weird CE related ship oversight

[Kuruni]

In UC, Space Ark and Reinforce are pretty much stripped-down Clop (which isn't really great ship to start). There are also Lysithea to Adrastea in V Gundam.

So it isn't really new...

[Zeonista]

Another problem in building new warships is the amount of time allowable for construction. New MS can be made in a factory on a daily basis, maybe a month or two for a fancy Gundam. Warships require years to achieve completion, or even undergo significant modification. So even if OMNI wanted to construct more Archangel or Archangel-influenced battle carriers, the events of GSD only two years later might have completely halted any forward progress. The subsequent political turmoil in the Eurasian Federation and the capture or destruction of manufacturing areas by ZAFT may also have ended any attempts to complete any hypothetical warships under construction.

[JEFFPIATT]

Since a lot of the CE universe emulated UC. OMNI decided to refit all of the old ships to better deploy ms. the two smaller classes just get em catapults bolted on outside the existing hanger hatches.Drake class has them attaced to the missle pods, Nelson class (refit) has the catapults on an new mount. while the Agamemnon class (refit) actually had the nose of the ship cut open to add the catapult. it was just cheaper to refit the fleet then build another class.

[Antares]

Yeah I would also suggest that it was a combination of lost prestige for the Archangel (wasn't it constructed at least partially with Orb's backing, which might not have been as forthcoming between GS and GSD). Seeing as how a good half of their space fleet was wiped out, maybe the effort of reconstructing the fleet up to a new line of fleets would've been too much of a burden to their economies. Older ship types might've been more affordable with everything else going on.

If we assume Logos took an active role in the rearmament efforts, projects like Destroy would've been much more appealing to their Blue Cosmos backers (i.e. terror/vengeance weapons). The timeline also is tight, as has been mentioned by quite a few in this thread, to divert resources from other lines of production (that might've been seen as more important). We should note, though, that at least a part of the Feddie space fleet was refitted, with catapults (as mentioned) and with shield arrays (the latter of which which ZAFT didn't have, and which could've been a major technological leap in terms of fleet tactics without the need of new battleships, if it hadn't been so poorly handled in the show).

I also think it's somewhat plausible to assume that the Feddies gave up bigger guns at the bargaining table of the Junius Treaty (historically speaking this would be typical), while continuing its clandestine projects as a nasty surprise to the Zafties. ZAFT, of course, somehow could find the resources to roll out a completely new line of MS within a few years, and could do it publicly within the limits of the Junius treaty (if I recall correctly). That suggests the treaty left quite a lot of leeway in terms of MS and MA construction. Looking at the Minerva, its smaller size might indeed be within the bounds of the Junius Treaty, while the ship the size of the Archangel would not.

[MythSearcher]

I guess 1 reason might be that the Archangel wasn't exactly a fast ship cause in SEED the Nazca Zaft ships could easily catch up to it. Its a very weak example though.

PR might have a lot to do with the Archangel class as the original ship defected and the 2nd was commanded by Blue Cosmos head honcho near the end of the war...

Atmospheric re-entry capable ships for OMNI/Alliance be damned!

I must say, if PR is the reason, then we'll see a lot of similar technology yet completely new class ships.
Design something with the same tech, same equipments, maybe even get upgrades, and ditch the poor PR looks. Its not that hard, really, look at the Minerva having most of the tech the ArchAngel class has, and upgrades as well.

Efficiency is usually the major reason in military hardware, the AA class just does not seem to emphasis efficiency at all, just strap a bunch of newest and most expensive tech together, bravo, you have a powerful yet completely cost ineffective ship.

That and also the arrogance of the Earth leaders. "Hey, we can use nuclear weapons, who need MSs any more?"