Grundfos, not exactly the new water pump kid on the block, has a system which includes a small 110 ac pump, adjustable timer and smallish manifold/thermostatic valve. Pump/timer are installed in the water heater tank area and manifold is installed at bathroom furthest from the water heater.
Timer is set to come on at say, 6 am, moving hot water from the heater tank to/through the 'open' manifold. The manifold allows incoming water to be returned to the heater tank via the cold water side. At 140 F, a thermostatic valve in the manifold snaps shut.
Bathroom now ready for first shave/shower with immediate, hot water. Pump times out in an hour, or so, after everyone has gone to work, but is adjustable.
Advantages: No wasted water while waiting for hot, and no expense running separate 'return' piping from bath back to water heater.
Any takers, doubters, or ------------satisfied users?