Wirelessly posted (BlackBerry8100/4.2.0 Profile/MIDP-2.0 Configuration/CLDC-1.1 VendorID/100)
I can't speak to most of your problems, because I don't have similar difficulties with my Pearl. But I do have the problem with delayed answering. When I press the button to answer the call, there's a delay before the other person can hear me.
It's not like that every time, and the delay is only one or two seconds at most. Usually I ignore it and i've gotten used to just pausing before answering.
I've heard that some people have taken their phones to the tmobile store to get this fixed, but I haven't tried that myself.