Some things have come to mind recently that i think could enhance player experiences in game, and curating one

Firstly, a mechanic to manually shift gears in vehicles, a simple "gear shift up" and "gear shift down" mechanic. This could make driving more engaging, and come with the benefits of getting up steeper hills on a lower gear due to the traction

Secondly, for game masters. The ability to "flush" the contents of a structure, making it empty like in A3, so that it can then be fully populated by a curator/mission maker. Perhaps on top of it the ability to save custom interior presets for structures to make it easier in the future.