Judging from what has been said before, I don't think J&L have that specific a plan layed out such that they can tell you what the game will be like 'when it is done'. Lots of ideas, sure.
I'm guessing we will see lockpick tools for getting through gates. Lock picking would probably take some time, and be dependent on skill/type of gate. Picks would probably break if you 'fail' a pick, and if they cost a wrought iron per set, that would discourage low level alt-pickers if the skill level required is high enough.
I think we will also see something along the lines of a disguise ability, brought in along with/after identification is changed/updated.
Hmmm.. Myself, if it can be balanced in some way, I would like to see the possibility of hiding ones hearthfire legitimately in some fashion. To my mind, a real thief, who uses his main character to steal with, must at a minimum consider layered brick walls. Even that would probably be pointless if somebody like raephire came knocking. Sure, we will probably get stone walls in the future. But this whole up the anti thing can go on indefinitely. At a certain point, it gets a bit 'un-thiefy' if you know what I mean.
Maybe, if a thief could create a hidden hearthfire somehow, such as inside a tree, or a log, using a certain skill, but it degrades within a relatively short period of time. Then, you would need to go out and put in a new one. These hearthfires could be resistant to being located via ranging. Maybe, discoverable within a short distance, but otherwise not?
I'm not sure what can be done here, but some kind of alternative will be needed in the long run. Ideally, something that favours the player who is prepared to shift around, actually risking their lives online to hide here and there over a course of days.