If you go to skinnier tires, you'll go faster for cheap.

However, it sounds like you've made a sort of psychological transition... you want to be a roadie

Ride some. See how they feel. (I have not found one that doesn't make me irritable after 30 miles - maybe I have some "core muscle" issues so I don't do the aerobic position well ??... we'll see what spring-semester-yoga can do for me. Sitting poses give me *exactly* the same bad mood...)