Getting higher quality textures would be the next big step in realism for IF.
Getting more detail in terrain textures when descending to land or when you are doing VFR flying would improve the flying experience for sure!
This would obviously require more data transfer to your mobile, but who cares while on wifi?
It could also be adjusted by a slider for when you must use a mobile provider data connection choosing a lower zoom level terrain detail.
If I am not wrong IF uses 15 zoom level currently while other sims, when using ortho images use 17+ zoom level, hence the better results.