Right, I think pickpocketing/lockpicking work better as a singular "security" skill. Pickpocketing is too unimportant. It has no real gameplay benefit beyond allowing you to attain meaningless amounts of gold (as if that's ever been a problem in TES). I don't see it as being large enough in scope for it's own skill.
Lockpicking, in Skyrim, isn't that important either, but I see more room for improvement than I do with pickpocketing. Lockpicking is just as much a navigation tool, opening up new paths for the player to explore, as it is a treasure hunting tool. More focus on the former implementation instead of it just allowing you to grab a few more gems every dungeon would be nice.
First, pickpocket is not unimportant. Why? You come across a group of bandits, 3 standing right next to each other, you realize there is NO possible stealth route, but you could A) disarm them all
B _)reverse pickpocket an ebony dagger with high enchantments on one of them and slip a frenzy poison/ nightingale subterfuge on their skin or C) place poisons on two of them, killing them, and then slit the throat of the last man.
The lockpicking tree is nice, it may not be nice for you, but its nice for me. I don't see the point of putting every single perk in combat based skills only. I don't look at this game through the prism of combat only.