Its been like this for me since the begining, GPU and CPU loaded almost to 100% and 100 degrees temp(rig similar to yours), but the game still runs like shit. Very poorly optimised - if at all, lol.

Pretty much everyone has this issue. It's just too early in the alpha and not a big enough company / engine to expect too much at this point :) optimisation will be the last thing done before release sadly. Perhaps adjust your fan curves if that's something you are comfortable with.