A lot of focus on stability and reducing lag would be good. But name changes too (they've already started working on adding support for name changes in 1.7, we will see it in a later version)
Exactly. It isn't much for the amount of time and effort gone into that content, therefore the money you do make is just something to motivate you slightly, it isn't some way to be making profit off of sites such as PMC, just a way to keep going.
Being able to integrate the users on my server with the users on my site, so, every Minecraft user on my server can use the same credentials to access the website.