Seems excessive and boring to be honest.
IRL a person can learn to pick locks fairly easily, and with rakes, bump keys and combs makes it trivial.
I think DC13 for average locks, and DC18 for exquisite ordinary locks is fair. Trained skill only. Assuming done without time constraints or distractions.
If you're trying to do it quick or while being shot at you should absolutely expect DC25 etc..
Naturally anything that's really worth locking up tight will have secondary puzzle or magical countermeasures too.