Ye, well the point is: I just don't get why I should take alteration as a main skill..You only get to be more tanky, but isnt destruction far more usable then..? Being stronger instead of some survivability?
I've been playing something between a spellsword/battlemage, so others might have better info, but my experience has been: destruction is OK, but not great for big/fast damage (on expert/master). You need several perk selections to deal reasonable damage. If you've got conjured atronarchs (or better, daedra), it's a good complement, but most of the damage will come from your summons. It's good for minor to mid-level fights, but you'll need to spend a lot of time running away from bosses or tougher creatures if you don't keep them occupied with summons.
I haven't enchanted anything yet, so it might be possible to buff the damage. There are a lot of enemies that can kill you in 1-3 hits, and you might need 10x that or more to kill them.