Some additional thoughts...
I've gotten huge gains starting out by doing a lot of intensity with pretty low volume... very similar to you. The problem is that this peaks quickly and then plateaus. Even though I later did long rides as well, something was missing. I didn't see additional improvement until I avoided the high intensity stuff altogether for an extended period, just doing endurance rides. This is base training and it's a good idea to not avoid it. It's actually pretty easy as well... you can do a lot of volume without getting too stressed. Then map out a schedule of build periods working back from your target events. Friel and others do a pretty good job of describing that. IME it doesn't take much training to get the high intensity part, once you have a solid endurance base.