Well, if you want a lighter, faster bike, you are probably talking about one a road bike. Road bikes generally have narrow tires and are light. They have responsive steering. They come in several forms such as "sport" bikes or "performance" bikes or "racing" bikes.

These bikes will work well for your longer rides. They will also allow you to tuck down and be more aerodynamic. They can be very comfortable too if the bike fits you well. Good fit is critical. One of the big complaints with these bikes is saddle. Many people find the saddles to be quite uncomfortable. The trick with saddles is to also get a good fit. Doing so is often a matter of trying various saddles until you find one that works for you.