I agree with most of that to some degree. I didn't really mind he was a bit dumpy. It's not like he was carrying junk in the trunk. It's no secret fans hated the killing the parents angle. That was contrived and unnecessary, and spoils their relationship for me. In fact I'd call it one of the worst ideas ever done for a CBM. Even script writer Sam Hamm disowns it. The Prince stuff was forced in by WB as a marketing ploy. Burton didn't even want it in there. Things like this are why Burton made it a condition that he had more creative control for the sequel.
The flesh make up thing was strange. The only time I've seen Joker do that is when he's disguising himself, which he clearly was not trying to do in the movie as everyone knew he was Joker. I mean he even announces himself as Joker on TV when he delivers that message about dumping 20 mil on the crowd at midnight. I did hate that he kept covering up his clown visage like that because his Joker look was great. The Vicki Vale stalking thing was just bad, and a waste of time that could have been spent on more interesting things. 
The Batman feud, have to agree there, too. Only one proper scene with Batman and Joker face to face in the movie, that's the end, and it's basically Batman wailing on him for killing his parents. That was a big disappointment for me, and doesn't encapsulate the Batman/Joker relationship for me at all.
Not to go off topic, but him and the Joker from The Batman cartoon are the only two I can't stomach visually.