One man training?

[Fred1956]

I have set out to get better, smoother, & faster on the bike. At 56 years old I'll never be what I once was but I can be better than I am. I seem to end up riding /training by myself a lot due to work schedules, ride locations and time schedules. I am blessed to have 300 acres of single track right out the shop door so if I can stay healthy I can wear the bike out right here at home. I scramble my loops + run them backwards for realistic speeds & so I don't get 'track smart'
Currently I am using an I-Phone app that GPS tracks my pace, time & distance and it Bluetooths to my Scala Rider headset on my helmet so it 'coaches' me every minute as to my elapsed time, speed average & distance. I also use it to coach me on my power walks through the woods. (+ I get to listen to my music in the background). I realize the safety aspect of riding hard by myself, so I let the wife know my loop and come by the house regularly so she has an idea of when & where to come looking for me should I get off schedule. Currently I have set a walk goal of 4mph for 2+ hours, last walk was 3.7mph for 1 hour & 15 minutes. This is following my single track loops so not on a flat track and some of the climbs are brutal My riding goal is to just get faster for longer, currently managing to go 1 hour & 15 minutes at a 13.7mph average as reported by the tracking app. This includes my slip ups, lay downs, and 'kill the bike/restart moments'. I'm hoping that seat time & endurance will get me smoother and eliminate mistakes. 1st riding goal is 2+ hours at a 15mph pace and then work up from there.
My question....are these realistic goals? What is a good speed & elapsed time to work towards? Any body have tips to stay 'pushing' during solo rides? Other than using your buddies to push yourself, what do you use? I'd love to hear other people's ideas & techniques. I'm not looking to go 'pro' and I do mostly hare scrambles of 1-2 hours in length. I'm going to do most if not all the remaining National Enduros so I'll get some long ride days currently a C50+ class rider. Let's hear some ideas & techniques..