I've taken a rising main cold water feed to the bathroom for the powershower, I'm thinking I'll T-off for the basin and toilet (all temporary plumbing) and remove our entire hot & cold water systems today, immersion heater, cold water tank, all pipe work etc. I feel like I haven't thought this through enough...
I think your main concern is just pipe diameters and sensible routing. Remember that every T and elbow adds an equivalent length of pipe which reduces flow rate.
I've taken a rising main cold water feed to the bathroom for the powershower, I'm thinking I'll T-off for the basin and toilet (all temporary plumbing) and remove our entire hot & cold water systems today, immersion heater, cold water tank, all pipe work etc. I feel like I haven't thought this through enough...