As far as Jarjar goes, I don't think it would have made any difference if he was CGI or a man in a costume, as you say his character just isn't believable. Personally I just don't find that type of humor (slapstick I suppose you would call it) funny. But then I don't Jerry Lewis funny either. I guess you could call Jarjar an intergalactic Jerry Lewis.
As far as Jarjar goes, I don't think it would have made any difference if he was CGI or a man in a costume, as you say his character just isn't believable. Personally I just don't find that type of humor (slapstick I suppose you would call it) funny. But then I don't Jerry Lewis funny either. I guess you could call Jarjar an intergalactic Jerry Lewis.