Quote Originally Posted by salsabike
Here's yet another thought, although I realize this raises a whole new set of issues (and money). I too average 13-14 mph, and my spouse about 17 mph. But we do a lot of tandem riding, which we both love and which smooths out the speed differences nicely. We ride on our single bikes by ourselves during the week, and do 30-60 mile tandem rides on the weekends. It's a blast! If that seems worth a try to you, read up a little on the basics (how to start, stop, who does what) and then rent one for a day. That's what we did, and we just loved it, and still do. Otherwise, what CA_in_NC says seems to make a lot of sense.
This is a really great idea too! I'll have to look into this. Thanks for all the ideas.