They're reading this thread, don't worry. I made sure to send it to them so they could get community feedback.
I'm going to argue your recommendation of getting rid of the trick bank, however. It's very important for Trick It players to not only see their combo (and their most recent trick) but seeing the current trick -- while in progress -- is also important so that you can avoid duplicates. This also matters in Race It where you want to maximise your boost earned from tricks, again making duplicate tricks an important thing to avoid.
It's just like how you need to see the >>>chevrons<<< to know when to trick so that you don't lose your TRICKY state.
I want a HUD-less option just for cruising/free riding, but now, after having spent dozens of hours with the game, the HUD is a serious necessity for any sort of competitive play, in my opinion.