Welcome to the forums
Yup, if you want a kickass, tough as nails tank by your side, the "Frankenmonster" is an absolute must-have. Follow the questline and eventually you'll meet a necromancer who'll get you started. If you somehow get stuck, there's the help forums you can browse or simply make a topic and 9/10, you'll get help.
As far as melee/caster goes, I played trough the game the first time as a 2h warrior, with firewall and missiles and it worked just fine. It's all about investing points in skills you find fun to use. Money shouldn't be a big issue in the game, especially not once you get your tower going and you can respec straight away.
The only hint I could give you is to keep your Vitality at a decent level. Spirit isn't all _that_ needed if you invest a point or two in "Mana Leech" so then it's all up to strength and intellect.
Have fun!
- Merdarion
