It's a good reason to use only connies though.
The writers probably had a fleet of Starfleet's best in mind, like the E was.
Just like the destruction of the Yamato on TNG or the Odyssey on DS9 wouldn't have had as much shock factor if it had been some random Excelsiors. Did they comment on which ship was supposed to be the Miranda?
I'm pretty sure a Miranda have looked gorgeous though
I think so too, and would have liked to see that. One of my most favorite changes was in one of my least favorite episodes, "Charlie X". I liked how they showed a "live action" version of the ship seen in the TAS episode where Spock was dying. I'm not sure, but I think it was "The Pirates of Orion".
Nah, it was "More Tribbles, More Troubles". The ship from "Pirates of Orion" was the SS Huron, a different design. Both ship types are also in the ("un-canon!"
) Star Trek: Of Gods and Men.
A TOS Miranda is in the (unfortunately utterly terrible) fan film "Blood and Fire". The story and acting are, sadly, horrific but the CG is great:
(pic borrowed from Trekmovie.com)