-Greedo shooting first... It never ever will look "right". The only way that scene will ever be normal or look realistic is if Han cold-bloodedly kills Greedo to not have to pay-up to Jabba. No ifs, ands, or buts to this.
-The weird disipating (sp?) smoke on the AT-ST that Chewie blows up shooting it with his AT-ST. ****** effect.
-Luke/Leia's swing that's impossible... Just don't like that they leave the barge via a means that, unless there's some rigging unknown, it's not possible. I hate that.
-The "scale" of the Endor Battle... not that I dislike it, it's a great battle, but to me it's something I wish he would've added many MANY ships to via CGI. It needs much more clutter.
-Enhancing the Stormtrooper bumping his head... It's a mistake, the "clank" wasn't necessary to actually point it out. It was better as a hidden joke only dorks knew.
-Sy Snootles in Jedi Rocks... I liked the puppet. The rest I kinda like, but the puppet is better than CGI Sy.
-Vader's motioning with no dialogue... Cut the damn thing out. It's funny to see from my nerd POV but it's distracting.
-Expand the Yavin battle... Again, like Endor, I think more ships would do it well. I'd add some A-Wings, and maybe a couple other ships... A TIE Bomber or two perhaps. Just something to expand the battle.
I actually like Riekean's remark, the background art on Jabba's barge (reminds me of the neat details Lucas was once classic for but lacks in the prequals), and stuff like that...
The magnet I can take or leave... it is what it is.
To me, most problems came from the SE's and he even fixed the Luke scream one thankfully. That was atrocious.