Hall light fed from upstairs lights (as it is double switched); conservatory lights fed (via an FCU) from the downstairs ring (as that could be extended into it easily); downstairs heating valves and underfloor heating pump fed from upstairs (as that it where most of the valves and the main pump are) and cables down to the wall-hung boiler. No other oddities. All down on drawings for the future.
I can highly recommend having the hall/landing lights fed from upstairs rather than downstairs. When I came in during the early hours of the morning, the hall light blew as I turned it on and tripped the breaker. Opening the kitchen door and putting that light on meant that I could see to disable the alarm before it went off and woke all the neighbours!