If you want to see old maps reworked so that their achievements are slightly easier to get then you should just say so cause that's all you'd be accomplishing with these suggestions. Nobody but achievement hunters gives two shits about Thief Maps.

If you want people to be more engaged with maps then the best thing that can be done is to change how RNG functions. For their entire lifespan, map RNG dictates exactly how much gameplay you get at a time which is a terrible feeling; absolutely no one enjoys being kicked out after one trash pack or boss battle, doubly so if you have to complete multiple maps to even spawn a portal.

Instead, this RNG should only be applied on your loot rolls so that you can actually experience a full run of the content as long as you don't die. You get the dopamine of a successful run and also the rush of finding out what's in your reward coffer. Hell, you can even expand the experience to apply bonuses to the loot depending on how well you did. Something like that would be quite refreshing for content that has just been reskinned every single expansion.