For further customization, you might even create whole new items suited to the person (some people want particular set items to look a certain way, not always cheating).
As for giving mana to warriors, etc, I'm pretty sure it's possible. If you type .exporchar (.exportchar <charname> <whateveryouwant>.txt) as a GM, you will get a text file in the main directory of the server filled with the values of your character. You'll notice that caster characters have a mana= line, and warriors have a rage= line.
I beleive it's possible to have both on one character, but I never confirmed it. You'll have to find a UI mod that is multi-class enough (or whatever) and will show mana and rage in order to track it, but I'd suggest a test using the following:
Make a warrior and warlock character, export both upon entry to the world.
Open your "classes.scp" file (in your favorite text editor) and scoll down to where it (should say) "//Shadow Bolt" under the warlock section (just use ctrl+f).
Copy that line into the warrior's exported file, he should have some "spell"s of his own, just lump it with them. Add a mana amount to him exceeding the cost of the spell, and save the file.
Log into the warlock and type ".importchar <whateveryouwant>.txt", and wait for the "Done" message. Your warrior should now be updated, log on to him.
Then post here and let us know whether or not the spell works.
And before anyone calls me a deadbeat, I'd test it myself, but I don't have 24/7 access to the server.