I watched a few of the prequels over Christmas aswell and randomly thought I'd type my random opinions. I kind of agree that episode 2 is the worst, I remember loving it when I went to see it at the cinema. When you first see it (especially when you're young) it kind of overwhelms you with sheer spectacle, trying to take everything in and follow the plot, but the big difference with the original trilogy is when you watch it again later it doesn't have the same timeless rewatch value or slightly light hearted and campy feel.
The things I was disappointed by apart from the cringeworthy bits of script and acting were the descriptions and 'feel' of what happened from the original trilogy don't really fit, Leia saying that she remembered her mother and that she was a sad person, Obi wan saying that anakin was already an amazing pilot when they met etc etc. I agree about ewen mcgreggor (plus palpatine imo and a few others) being great in the films and them being the best actors in the cast by a mile. It was obviously a bad decision to use young inexperienced actors with Lucas who apparently isn't 'an actors director', as well as the bowel shuddering script at big moments.
I still like them though, I'm not all mr plinket about it even though it would be; they all have good bits that are great to watch again but episode 2 hast the least and just for waisted potential with the ham handedly handled huge jedi battle, awful romance melodrama and all the other bits that could've been cool, it has to be. But it still has cool stuff in it.
I really like the beginning of episode one; I think it successfully establishes a sort of noble old world feel, and two jedi getting into adventures etc when you see what they were like in the olden times. They really went for a similar feel with the naboo, chancellor and senate etc looking regal and refined that you don't really get a lot of in the original trilogy and I think it worked. The light sabre battle was also great imo, I don't agree with red letter media that it's not established properly, you know the guy is a sith and the good guys are jedi and that they hate each other for thousands of years, it works at the emotional level of the film imo and is a great fight. It is a roller coaster but so was the original star wars imo. I think it has the least bad script aswell (apart from when the poor kid is involved and the medichlorians bit) and don't even mind jar jar all that much, he's kind of annoying but wouldn't be if he wasn't around so much. The naboo battle is ok aswell (but I think it doesn't really work so well that both space and ground ones end in a slapstick way), the poor kid is more annoying imo and it adds to it that I feel so sorry for him because of being doomed to the fate of loads of child stars. Some of the cgi has started to look a teeny bit dated aswell.
I think they tried to keep the campy feel in later episodes and it didn't really work with the more 'grown up' subject matter.