Thermal store on thermostat and timer - so cylinder calling for heat is the only control over the boiler (timer will probably be set to either continuous, or off for holidays, or possibly a nightime quiet patch). (and boiler controls pump and pump overrun)
But what control of the rads?
There will be two radiator circuits (open plan main area kitchen & cloakroom wc, and bedrooms & bathrooms), and operated on "pump plan" with a further pump on each circuit.
The building layout is unusual with no obvious place for room thermostats, so I'm considering all rads fitted with TRV's, and the timer for each circuit just controls the pump for that circuit (with automatic bypass valves if all trv's are closed on that circuit).
This would mean the pump runs continuously during a heating "on" period, but power consumption of a pump seems to be about a lightbulb's worth.
From a user perspective, you have the hot water timer that needs to be on whenever you want water or heating (and is best left on all the time), two timers for each of the rad circuits, and no thermostats - just trv's. I've seen a nice 4-channel timer that wraps the functionality up into one neat little package.
(Other details that probably don't affect the overall picture - the main open plan area is on two levels and also has a woodburner (so main area trv's might be set to "off"), boiler is non-condensing oil- fired.)
Advice, suggestions, feedback?