With him successfully upgrading his status to a Chief Keeper of the Grand Library, Ashton can now stay inside the Library indefinitely. This means that he doesn't have to rely on the underground bunkers anymore to keep himself safe.
Additionally, the Gatekeeper said that he can make small changes within the Library. These changes are limited to moving shelves mentally, adding a single room like Aria's, relocating the Librarian's desk and other small things. It isn't much but it's a nice addition to his authority.
The fact that he had to be out of combat to enter the Grand Library still hasn't changed though. Not to mention, he'll appear at the same spot where he disappeared which might give him problems in the future. It doesn't help that he can't spread his perception beyond the library to check his surroundings. It's not like time become suspended outside while he's inside so that might really cause some problems for him.
