I have a larger ranch-style home with a similar problem -- very long runs
that can take a minute or more to get warm water, and then it gradually gets
warmer over another minute while it heats up a 100 foot of copper . For
appliances like the dish washer, it never would get hot water to it as it
would not run long enough to heat the lines..

The builder installed a 1/40 hp (1/2 amp) motor/pump and a timer and an
insulated return line to recalculate the hot water. I have it set so it
comes on before I get up in the morning and turns off after I leave for
work. It comes on again in the evening for a few hours and then turns off
for the night.

It works terrific. With the timer I am not circulating hot water 24 hours a
day. When it is running, the water is almost instantly hot. There are four
bathrooms and a kitchen in different parts of the house, so it would not
have made sense to try to install demand-style heaters in all of these
locations. There is a manual switch I can flip anytime to turn it on (doing
laundry during the middle of the day on the weekend, etc.).