The first one is not very simple, because GSX might have to decide which vehicles (stairs or not) put on parking even *before* you get there so, it cannot possibly know if the jetway would work, unless you get there, park and call SODE, which is what tells GSX if the jetway could work.
The variable passenger number has already being dealt with by exposing a control variable that airplane developers can write to, telling exactly how much crew they have so, we don't risk of GSX saying something and the airplane saying something else. Both FS Labs, Aerosoft and Leonardo will support this when the GSX update will come.