*** To start with, I know its only early Alpha, they come over time ***
I think the game need better Anti-Aliasing, Objects seem quite smooth on lowest quality.
Buildings course an obscene amount of lag also, Maybe walls could be batched into one solid object instead of 10? if not already doing it... It would be something good before you switch into Beta and release onto steam also
Sadly im one of these people who struggle to run it, and yes you can tell me to get a better computer but its not very easy for certain people... I believe optimizations should be made along side bug fixes, once something is optimized you wont ever have to come back to it later.