Currently when lockpicking, we get this 'bar' and can't make out how difficult the lock is to pick. Why not give us a roll, like when disarming traps? (seems to work nicely there) The 'bar' thing is DOS2, we NEED a roll for lockpicking.
Also, I shouldn't be able to pick a 'lock' in bunch of rocks blocking an entrance (referring to the rocks in front of the dragon's lair in the grove). Maybe a STR (Athletics) check would fit better here?
I also think thieve's tools should not be used up when you succceed on lockpicking, but only when you fail (due to the lockpick breaking).