You repaired the head plug leak , are you sure your screening was in place in the head cover?
    You may have to reach a compromise , which is most important to you ? If it's highway speed ,with lower oil loss and lower rpm, then a kawa pulley is the way to go . If you don't want to give up low rpm response then it's time to slow highway speeds to something the bike will handle  ,70 mph should be a max cruising speed ,unless passing, for a stock bike .   I wasn't aware that the speed limit in Texas was 75-80mph ,that's basically WOT = abuse for a stock Savage.