Topic pretty much says it all, I'm having trouble picking 1 crafting skill for a master difficulty run with my assassin. I'll be going dual wield daggers, also I'm using the PISE mod which makes the game quite a bit more difficult (any type of dragon can spawn at any level, more mobs are encountered in the wild and they tend to be higher level than normal).

I don't plan on abusing whatever skill it is I pick or blatantly powerleveling it/using alchemy potions to enhance it. I was leaning enchanting, but I simply can't make up my mind and I honestly don't want to/refuse to use more than 1 crafting skill.

I'd go smithing, but because it is ridiculously powerful (to the point where people call it an exploit) try not to abuse it.

Alchemy for poisons.

Alchemy for poisons of course. what kind of assassin doesn't use poison.

Enchanting is the most powerful, but alchemy is the most fitting for an assassin I'd say.

If you care much about RP'ing then the choice should be easy, go alchemy all the way.