I have been running it for a couple of days now and my experience is completely different from your's.
The battery always dropped 4-7% within 30 minutes or so. This is the reason for the million of threads we see on here about bumb charging. So no change there...
My battery life has improved by about 10% or so.
I charge overnight so I have no idea if that is slower or not. All I know is that it fully charges in the time it takes me to sleep

I have seen several reports of this so you are probably correct.
My phone is MUCH faster. It was fast before but now it's insane. I actually had to turn down the home screen scrolling speed in my Launcher Pro app because it was going too fast.
My quadrant scores went from 550-600 (with 2.1) to 1200-1400 (with 2.2).
Flash is working fine as far as I can tell. Everything I have tried it on worked great.
My browser speed is pretty much the same. No improvement that I can notice, but not slower by any stretch of the imagination.
You might want to try a factory reset if you are having this many problems. I really don't think it's normal.