Probably needs someone with more experience than me but I did get involved in a renovation project for a Hotel about 7 years ago. Here's some thoughts. looks like there's already a bit of design going on in the Summer house. Obviously requires at least one three phase board with various sub mains off it single and three phase. One to supply the kitchen
Each bedroom should perhaps have a single phase feed to a small Enclosure for at least 2 or 3 RCBOs supplying sockets, lighting and ventilation/aircon. Maybe 6mm~16mm depending on what's going in there? 5 amp lighting either side of the beds for a high spec hotel, Wall TV with a Cat6 supply to it. Hairdryer and mirrored light outside the bathroom. Shave point / toothbrush charger inside.
Emergency lighting in all corridors - probably fully maintained. PIR lighting if corridors are long to save power.
Solar panels on the roof to safe the client money and to help lower costs.
Three phase to kitchen equipment as the venue could be used for weddings and other events so plenty of power maybe required.
Power to a plant room to supply boilers and water heating equipment
Pool will require some power for cleaning maybe a 16A RCD socket somewhere and this needs to be fully signed up so some Herbert teaching aqua gym lessons doesn't plug a stereo into it and kill himself (there's a story somewhere about it).
External lighting to carpark areas, outside security and hospitality lighting and maybe patio heating under cover.
Power to Sauna for the mood lighting and Heater unit plunge pool have to look into the special locations. the sauna surprising hasn't got many Regs
