Might I suggest just a lowering of the DCs on tinkering? Having just played a herbalist, I can agree that the DCs in tinkering seem eye-wateringly high, even for common-or-garden made items.
It would open the field up to rogues more generally, without having to specialise in the one Perk that is already very good for the other bonuses.
It would open the field up to rogues more generally, without having to specialise in the one Perk that is already very good for the other bonuses.