I would say NZA, FlyTampa, FSDreamTeam, Aerosoft, Drzweicki are my top five I keep an eye on… Orbx, now mostly just operating as publishers, do feature a lot of great airports as well. I really am not a fan of the “factory” or “fresh” airports many produce (because it is much less time consuming, and probably cost efficient). I for one appreciate the cracked, rubber-marked, oil and fuel stained surfaces that 99.9% of airports in the real world have. There are some addons now that add the realistic runway and apron imperfections, which is a nice addition. The most detailed I’ve seen thus far for MSFS has been from the NZA team, who spend a crazy amount of time into getting the details and scope of their airports just right.