It’s all looking quite good. Return of the Jedi, while they upped the technicality of some of the effects work, it just hasn’t aged very nicely.
Yes the effects are problematic. You can see that they blue screened stuff on layers, with each layer having a different color shift. And there are some continuity problems on some sequences, fixable if you reedit according to the original intended scene sequences. This is specially noticeable on the space battle.