The more I look at doing some things to improve my riding, the more I realize I should structure my riding sessions with specific purposes. I do ride recreationally only, but because I don't race doesn't mean I don't want to improve and be able to go far and fast. I have read a bit about training for strength and speed and it seems to emphasize training aimed at competition only. I know it is applicable to what I am asking, but I don't want to turn my rides into a scheduled "training session" only and feel like a race horse.
What I already do:
I got the distance part down as I have been able to ride solo for 120 miles (taking some short breaks in between of course). I ride 3-5 times per week depending on work. One long ride on the weekends. My regular rides are either a 42 mile loop or a 62 mile loop. The longer ride is based on how I feel that day between 90-120 miles. All flat pretty much. Closest hills are about 2 hours away, and quite frankly doubt I enjoy long, slow, painful uphill riding. I average about 19 mph for all my rides.
What I want to improve:
I wished I was faster altogether for the same length of riding I already do. I wished I could ride faster for the same rides I do and still feel good at the end. I don't enjoy the feeling like I need to puke at the end. Remember, I enjoy riding just for riding, and I have not intention on racing/competing now or ever!
I just need a few suggestions of what/how I can incorporate in some of my rides to improve my performance and speed altogether.