Okay, here is my ruling on Thieves Tools and Lockpicks! As always, all rulings are subject to change based on what's 'fun' in actual play.
Delving Deeper v5 does not mention these tools, and therefore I will continue to not require them.
The closest to a definitive ruling is in DD v5 Heroes & Magic, page 40 (this is a quote of a quote
originally from odd74 member Daniel Wager) "It came about like this, one group had a dwarf who wanted to try picking locks with his dagger, so I had the idea for a Burglar class."
If original '74 dwarves can pick locks with daggers, then hobbet burglars can
definitely pick locks with whatever improvised items they can pull from their nasty little pocketses!
However: I understand that thieves tools are cool and you want them. That's totally fine with me.
I will put the ball in your court: Whenever your PC is in a situation where you think your Thieves Tools would be applicable, you can describe your actions to me. (For example using your tiny snippers to disarm a trip wire.) If I am convinced, I will give you a bonus. This seems highly appropriate to the spirit of old school gameplay.
To balance this out, I will "upgrade" some of the locks and traps throughout the dungeon.
The first dungeon level has been largely bereft of traditional traps and locks. That was an intentional decision. I wanted to use mostly non-lethal puzzles and easter eggs on the first level. Look for the training wheels to come off in deeper dungeon levels.