^Lol, it still doesn't make sense that he was more advanced in a trilogy that takes place earlier

The only difference is the jetpacks, and logically it makes sense that it would have those as a way to get into the ships it copilots.

They didn't give him anything that outlandish, and giving him a jetpack isn't something that I would call ruining his character. 

"logically it makes sense that it would have those as a way to get into the ships it copilots."

And then never use them again in Star Wars '77, Empire Strikes Back and Return of the Jedi? I agree the characters weren't ruined, necessarily, but they weren't given any favors either. It feels like a lot of the characters seen in the prequel trilogy were more like parodies of what we knew of them from the original trilogy. Not literally so, but everyone felt a lot less serious than what was expected.

As I said it was kind of an effects thing. Making R2 fly just wasn't possible in that capacity for the ot, at least not without a huge budget being devoted to that.

R2 is also literally different for the OT since the last things you see about him and C3PO is Bale Organa saying to wipe their memories and refit them since he gets them at the end of Episode 3.

^It was only Threepio who got his memory wiped

I say Threepio was ruined because he was temporarily a battle droid

No it was both, C3PO was just the one to comment "oh dear" when he heard it.

The acting - I think the worst thing about the prequels was the acting! Most of the main cast is made up of good actors (Even Hayden has done some decent things) but somehow they all seemed to just phone it in for these movies.