Several unique ideas

I have several basic ideas of possible champion concept and i wonder who sounds better:

1. Mana spender champion, who gets stronger by spending mana faster;
2. Champion who would level up in a different way than other champions;
3. +1 assassin (who is weak 1v1, but can easily move through map and have global presence);
4. Dedicated support, who binds to one champions and will always follow him;
5. Suicide fighter, who benefits from taking damage;
6. Critical strike chance based mage;