1) Where to move to? I want to stick with wordpress, for sure. ... What do you other Wordpress bloggers use? Self-hosted? Purchased-hosting?
If you feel up to installing and configuring wordpress on your own then purchase your own hosting. Let them deal with the headaches. At a minimum use a host that gives you shell access. If they give you that, they will probably give you everything else you will eventually need.
There are quite a few good ones out there. I use http://www.kattare.com/
. I highly recommend them. No problems and many technical customizations requests later (outside what is normally offered from a purchased host) they have been personal and quick.
2) Content shift. I love priesting, really I do. But I also love huntering. And enjoy my shaman...I have a ton of posts I could do on other classes, but I feel awkward hanging them all underneath "The Egotistical Priest" banner. .... So the question isn't "do you think it's okay if I start writing on other classes" so much as "do you think it's okay to start writing on other classes while still calling my site The Egotistical Priest?"
I think you should keep the brand. Self-hosting will give you the flexibility to separate the new content from the old. The simplest would be to rearrange your categories and menus to separate the content. People could decide if they want to 'add in' the new posts you are doing by choosing the right catagory. Or if you wanted to get complicated you could make it appear they are actually separate blogs while still being one blog underneath. For example priest.egotisticalpriest.com and egotisticalpriest.com where one is purely healing centric and the other is everything. There are quite a few possibilities but whatever you choose I wouldn't give up a brand you worked hard to create.
3) Naming? How should I rename the blog to fit the new content (assuming that's the way number two leans)? I want to keep the "Egotistical" bit. It seems to be unique and shortens neatly down to the nickname "Ego".
Maybe egotistic (two letters less!), egohot, egoblog, or even egotastic!