Two pseudo-OT things that I'd like to add to the ongoing discussion...
- It was once suggested that the Constellation class might be TMP-era tech taken to extreme; that is, it's the final "hurrah" of that level of tech, pushed as far as it could go almost to a cartoonish extent. The four nacelles and pseudo-kitbash nature of the ship, replete with greebles here and there, combined with Picard's lines about it being an "overworked, underpowered vessel" would seem to agree with this thought and I agree. Just as Miranda class ships are still valid in the 24th century, there could likely be found good reasons why the Constellation's niche would still render them useful. (Indeed, Starfleet seemed to be big on "we got 'er, let's use 'er" when it came to ships.) I would also agree with the notion that the Constellation was some kind of deep space cruiser/explorer.
- Registry numbers, for me, exist somewhere between a ship hull number and an aircraft tail number, best thought of as a "license plate." They were indeed kept quite organized in the TNG era but I have come to suspect there was an amount of intentional complication to their otherwise linear pattern. Take for example the Constitution class Eagle (NCC-956) and Constellation (NCC-1017) both being alleged contemporaries of NCC-1701. To me, one is special but two could form a pattern, and Eagle's registry was as far as I know, purely invented by Mr. Okuda. (I believe we have other incidences of lower registry ships being launched later than we think.) I suspect that Mr. Okuda and team, when possible, created and perpetuated oddities such as this just enough to give the writers room to establish whatever they wanted to about when a ship was ordered, launched, refit, and so on. The Tsiolkovsky would be an exception caused by production complications and there were likely others of this type, but Mr. Okuda almost certainly had his own internal logic for why there were so many NCC-4xxxx Excelsiors, for example.
Now to the original topic, I agree with others that the
Miranda class probably represented a sort of peak or ceiling for its design lineage. Assume for a moment that they're frigates; they may have been the best frigate Starfleet ever produced in terms of durability and reliability. Attempts to replicate or replace it (of which perhaps the
Centaur class was one) came up short for whatever reasons. When repeated efforts failed, Starfleet just kept building more
Mirandas. Newer built ships would have continued service, while older ones would have been retired and relegated to surplus yards. As others have noted, it appears that automation allowed the vessels to carry much smaller crews than originally intended, freeing up that space and power that would have otherwise been used for crew accommodation for other goodies. It's likely that that ships we saw in the Dominion War were a combination of active ships and ones that were pulled from mothballs to act as gunboats and then probably retired again if they survived the war.
Regarding the Jeep Wrangler analogy that someone mentioned earlier, I'll relate the somewhat apocryphal story of the Jeep Cherokee. Allegedly, the old Cherokee was built so well (and people so fond of them) that Jeep silently quit building them and replaced it with the Jeep Liberty because it was staying on the road so long and keeping people from buying new vehicles. Flip that around a little and militarize it, and we could see why a
Miranda class starship just couldn't be killed without a lot of effort.
Are they more dangerous than other ships? I'd firmly say no.