Personally i dont like how spells are in Oblivion (and actually in most rpg games) they are very linear which gives the impression that you use a laser gun or something, except the conjuration of course, which was the only one that i really enjoyed - so bring your ideas!! and of course i want to add that a mage is someone who should not run a lot, have to fight or even use stealth, otherwise why he is a mage, in an invironment he should be able to just use the right spells to do the job and nothing else, i mean when i m on the highest level and i still have to watch out for arrows and swords then what kind of mage is that?!!!
To summarise, the orchestrated use of the right spells is what a mage should need to do and nothing else, no fight, no stealth