Here's where I've landed on the matter... I'm now shifting consistently at 3350 RPM. I find that winding it out to 3800 RPM seems to be the end of my torque curve. Heading down the highway at 65MPH the tach sits at about 3100.
Then there's the tires...
I've also done the Toyota steel wheel conversion. I still shift at roughly 3300-3500 RPM. The last thing to note is the odometer just rolled over 300,000 miles. I put new timing belts on last year and rebuilt the oil pump. I don't think I'll ever see a lot of 'power' on the road but the car performs to my liking. I can pull a light trailer (trips to the tip) and hauling kayaks, etc. But I take this car for what it is - it's a recreational car. We use it for exploring backroads, adventures and short highway trips. It used to be my highway commuter but my company now provides a car.
So, for me, shift at ~3300, cruise at ~3000