Ok, so I did another 18 miles last night and started with the saddle up 10mm. Immediately felt the saddle was too high, both riding and with a foot down at stops, and the bike was more twitchy - left toes had started the hot foot and numbness.
Stopped mid ride and lowered the saddle 5mm, so that it was up a net 5mm from the start of the ride. Sweet spot! Left toe numbness subsided. Bike still twitchy, but I'll get used to that now and solve it later with a longer stem as my fitness/posture improves. When I rode a couple of nights ago before raising the saddle (but after having moved it forward 150mm), the muscles right above and in front of both knees felt overworked after the ride and when I woke up the next morning.
This time, nothing abnormal hurt. Just felt like a slow, old guy had gone on a bike ride when I got up this morning. I'm going to leave it there for a while.
Glenn