ADS for optics without zoom with 2.2X zoom is added now. How both ADS FOV and the sensitivity scale in this game is a real mess. It might be some reasoning to it when digging some more, but nothing like any other game. Current calculations are not 100% perfect, but within 0.1-0.2%, so the lack of decimals is more of a concern.
I'll work some more on it to get it perfect, and add scopes and vehicle when I get those.