There are some issues with replays, the biggest one being that they are different on 32 bit/64 bit/big endian/little endian systems. So it's difficult to do real sharing of replays. Here's the issue that represents the fix for this:
http://code.google.com/p/vdrift/issues/detail?id=4
Your ideas are definitely good ones and we'd definitely like to have a more complete replay selection screen, etc (see this issue:
http://code.google.com/p/vdrift/issues/detail?id=38), not to mention some other issues exist with replay such as this one:
http://code.google.com/p/vdrift/issues/detail?id=47
Feel free to leave comments on those issues, or continue posting your ideas. Just wanted to let you know we're already thinking about some of that stuff.