Oh, I am well aware of the age issue. I keep telling my friend that he can't expect me to do what he does - like riding for miles at 27 mph! I think my very fastest speed on a flat road (with a little wind help) was 28 and that lasted for about 1 second!.
But what I would like to do, and based on what I've seen posted by other older riders and talking to people, I think should be possible is:
Do my first 11 miles at AT LEAST 15 mph without feeling like I'm pushing hard.
Do those same miles while pushing hard (but not max effort) at 18 consistently.
And at a maximum effort, pass 20.
I'd also like to climb hills faster. Climbing more hills and steeper hills hasn't seemed to translate into climbing my normal hills faster. So I'm guessing I need to deliberately be more aggressive on the hill training, not just do more and harder ones.
For example, I climb a section of Diamond Head and if I just take a comfortable pace (not that it is all that "confortable"!), I still find myself going 5.7-8 mph on most of the hill - same as a year or more ago at the same effort.
So I'm not looking to ride like the young folks, especially since I'm not training like a racer would. I just want to see some speed improvement as well as carry speed for a longer time. Nothing huge, just not me in a danged rut and certainly not seem to be slowing down yet!