Cool! Looks interesting.

I like the blue touches already in the room, which reflect the brickwork. Agree with lots of creams/ neutrals, just adding some blue in cushions, artwork. Maybe a bluish/cream rug, with a subtle pattern, not a solid color. Also I think the lights are a little lost. The high ceilings could take some quite large shades, maybe drums. And I agree that the central column could be painted to become the focal point as stated. Either white or quite a dark grey/ blue, ( it might darken up things too much, but it's only paint, can be changed). It might be sinful but I think I would replace it with plaster, then paint it. Finally maybe a dash of 60s burnt orange or mustard if you want to want to keep the retro theme.

your dilemma is difficult to understand without more information and would be so much easier if we had the original whole house plan with dimensions and showing front and back entry, and views, size and position of prop0sed pool and all existing windows and doors, any walls doors or windows that can't be changed and direction of north...as well as any special requests for the kitchen

Finally the job of replacing the spa bath with a normal bath has started. Firstly, part of kitchen ceiling removed to undo spa waste, then row of tiles removed to jiggle out the spa - no good! Plumber had to cut spa shell in 2 with grinder to remove. New replacement bath, same make and model, now installed, waterproofing done, tiler called in to assess the retiling job. I thought I'd be clever and order some white replacement tiles to help - ha, tiler says they are a slightly different colour but have just enough of originals to finish the job. Heading in the right direction!!