Well I dont have ANY of those problems, so its unique to your unit, or your configuration. Those that have similar problems to you probably have a similar setup.
Keep in mind I don't use sd card or a backup camera.
I have zero reboots, in fact I only had maybe 2 in the last 6 months, prior to 2.0.
Call hangup is 5 to 10 seconds, if that. Zero problems with button responses, nothing compare to prior 2.0 which is what im comparing to. For me the presses are almost instant after touching them, providing you touch the button in the right area.
My only complaint as stated before is the bluetooth mic sound volume.
So I would say there is an issue with your camera, SD card, or the unit itself.
So in that regard, it makes sense why your having issues and im not.
I use bluetooth, xm module, but I haven't had a use for the sd card slot or dvd player given I have an iphone.
Sounds like you do have the call hangup problem, but maybe its not as bad as mine. And you would have the SD and camera problem if you used them I imagine. How can you say you dont have it if you havent tried? I have used several high quality SD cards, and I have a 120 dollar Kenwood camera, so its not my components.
You say you have zero reboots, then say you had 2.
You say yours isn't sluggish, but only compared to before (implying it still may be sluggish, i.e. almost an instant).
I think you are just being far too forgiving of the unit. You have the same problems I do, you just are not holding the unit up to a decent standard.