Most of the popular servers on the server list have raids constantly going on. They aren't the huge raids you might see on Live, but some of them get up to 20-30 characters in them or so. They are still quite a bit of fun and a nice challenge in most cases.
There are people to level with on most servers if you can find a group, but most are also fairly easy to solo level. But, if your PC can handle 2 or 3 boxing, and you enjoy boxing, then I would recommend it. It is free to have as many accounts as you like, so why not?