On Thieves tools and Open Lock:
You have to have some points in Open Lock in order to be able to use Thieves Tools. The issue comes in where a single point investment gives access to the highest levels of gear, spells and consumables. Just because I took one point in UMD doesn't mean I should be able to cast from 9th level scrolls. I would like to see some gating on Thieves Tools. The +10 and +12 varieties, while expensive, drop far too often as loot in Har-akir. Honestly going through that domain nets me far more picks than I have to use.
I'm not really sure what the answer is. Maybe making knock unable to be self cast or only give a bonus up to current OL ranks. I don't think that's fair to magical types who seriously invest in the skill. Maybe I'd like to see more class locked gear to protect the rogue niche. Either making it harder for non-rogues to pick or increasing DCs to the point where it's far more beneficial to run a rogue in your party are some options as well. Current OL DCs are fairly low imo. So much so I cut the skill out of my build significantly. (15 ranks)
Consider mirroring with locks how traps works. After a certain DC (35 in the case of traps) only rogues are able to attempt. With that being said...
On traps:
Traps in dungeon's suck and I don't mean in a "they're difficult to deal with" way. I mean it in a "they're a six second delay that poses no risk." Trap locations need to be randomized to more locations to make dealing with them more of a priority and the area's of effect increase to affect the whole party. If you set that trap off, it should mean something. Think gas and electric traps, traps that trigger scripts, additional mobs, throw down dangerous spells like horrid whilting, incendiary cloud, mordenkien's disjunction.
Traps are great for PvP. Flat out. You'll kill who you're after. The issue is that's not very satisfying for your victim. I'd like to see more crafted traps that are able to hinder opponents so that RP following can be lengthened instead of "BZZZZT- you're dead." For some classes- it can be very hard to disable and so you can feel forced to try to drop them as quick as possible. If more options where available, Silencing Traps, Baleful Polymorph traps, Invis purge traps, the list goes on, you can tailor your appraoch to the target. We already have items in consumable form for these effects, it should be entirely possible to make traps from something like a "Witches Cauldron" or "Dust of Appearance."