Welcome To Bike Forums, Smtty!

IMHO, you purchased the wrong bike from the start. If you are primarily interested in speed and exercise on paved roads, then your cycling interests just screams out, road bike. Not mountain bike or hybrid, but road bike exclusively!

A road bike will allow you to personally challenge yourself in terms of speed. You can gradually increase your distance and the speed in which you cover that distance. Of course, you could do the same thing with a mountain bike or a hybrid, but you'll move faster on a road bike. Increasing the distance of your treks will make it necessary to take advantage of the drop handlebars and the variety of hand positions they offer.