Yep, there are still many 1st-gen plane models that need updating. It's no small task, and only HTC staff can do it (according to their list of things they'd like to get done).
Maps are, for the most part, player made. There are many specialty maps for special events and the Axis Versus Allied arena, and anyone can use any of them in a custom arena. Making a map for the Main Arenas is tedious and has very strict rules that must be followed. There are not many people with the time, patience and talent to make worthy maps...but there are some, and they are working on them.