You actually thought ROTS' ending was "very good" and "on par with the OT"? That's asinine. It was basically a rushed, poorly-executed attempt to tie up all the loose ends left dangling and cover over the legion of unresolved plotholes with a thin layer of pretty CGI and overly-contrived, cartoonish, boringly long lightsabre battles. Add the this total failure Padme's "losing the will to live," Yoda's undignified frog-hopping, Palpatine's transformation into a laughably bad self-parody, and the unwillingness or else inability to adequately set things up for the next movie (ANH), and you're left with nothing more than a steaming pile of sith. (Haw haw.)
Personally, I've come to see TPM, as unwatchably bad as it is, as a lot closer to the spirit of the OT than either of its sequels. At least that one felt a little like Star Wars, even though it was cringe-inducing and stupid. AOTC and ROTS have just chucked sincerity and fun out the window, and have settled for PS2 video-game sequences and "romance drama" that feels like a twelve year old wrote it.