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Bit late to this but if you go for underfloor heating make sure you seal the feet of any wooden furniture you've got - it's normal to leave the feet of cabinets and chairs unvarnished, but wood (especially oak) will dry out and change shape if it's got constant heat running up the grain from contact with a heated floor.
My ex's dad is a cabinet maker in the North East - we spent one summer driving around helping him to collect old furniture he'd made, the owners had since installed underfloor heating and the cabinets needed some serious repair.
Wet for sure, only considering it for the ground floor. Haven't got the ceiling heights on 1st and 2nd floors.
Ground floor plan is as attached.