For me it’s the second worse. AOTC is just totally unsalvageable and is the absolute low of the franchise. ROTS is a little better. I’ll agree, of the PT, it probably has the best “character work” as you put it. But what really kills the film for me is the absolutely terrible handling of Anakin’s motivations for turning to the Dark Side, the very fast actual turn and embrace of it, and him murdering children. Follow that with the way the film totally craps all over continuity with the OT and I just can’t find any real enjoyment in it.

I find TPM to be the most bearable prequel but a lot of that is because it looks the most like a Star Wars film and it’s so far removed from the OT that I have an easier time overlooking its inconsistent continuity. Also, I actually like Qui-gon and Darth Maul (as much of a wasted character as he was). I also have a little nostalgia for TPM with the marketing and the build up and excitement for new Star Wars (I remember cutting class early to stand in line for tickets! I was in high school at the time). By the time AOTC came out, reality had sunk in. And with ROTS, I was just hoping it would at least kinda stick the landing. But it didn’t.

Jedit:
I don’t know why but I feel the need to point out I’ve not watched any of the PT in well over a decade. The closest thing I’ve done is read Darths and Droids and watch the Auralnauts’ edits on YouTube. And honestly, that’s how I prefer my exposure to the PT to remain: as parody. Those are genuinely entertaining and fun. Something that cannot be said of the PT in its purer form.