I always take alchemy. The potions you can make are stronger than the ones you can find, minus the cheating "ultimate" potions that restore all of your Health/Magicka/Stamina.
The potions I usually mass produce and use are Damage increasing potions of whatever weapon I use, paralysis, invisibility, and health/magicka/stamina. Of course smithing also. I would use pickpocketing potions if they weren't still glitched.
I can't help but feel more and more skills keep losing usefulness though. Compared to Oblivion the alchemy in Skyrim is weak, exept for the restoration exploit of course. I could do hundreds of poison damage in Oblivion, and using a healin over time potion I could swim through lava and not die.
EDIT : In fact it is arguably the most powerful skill in the game. It is by far the most versatile.
Definitely if used right. I mean what other skill can increase every other skill besides itself? none.