You may be planning to do this already, but I think more needs to be done to make the dubbing feel more integrated into the scene. Right now, it feels like a clean voiceover, as if this was someone doing a video essay on YouTube, especially compared to how Qui-Gon and Obi-wan’s dialogue sounds. I know there are audio effects through Audition and other audio programs that can help add an echo to dialogue to make it feel like it is being spoken in different types of environments. Alternatively, someone once told me about an older technique called ‘worlding’ where you would take your ADR, play it out loud in a location similar to where the lines are spoken in the scene, and rerecord them in that location. That way you are getting additional ambiance and echo that helps ground the dialogue naturally within an environment. Your Boss Nass scene actually has a noticeable reverb.

So, for example, in the Bongo scenes, you could perhaps take your new Jar Jar dialogue, play it out loud inside your car and rerecord it. Also, for how much Jar Jar moves around, I wonder if recording some foley for when he face palms, rests his arm in the chair, slumps down in his chair, clothes jostling, etc., could help sell the new dialogue as well.