am assuming this is a concrete structure, when shifting service toilet to utility area, and if there are apartments above, then running extra lengths of supply/drainage lines & introducing a structural sink slab (if this is concrete) under the new location can be charged extra.. it will be easier to divide the 3rd toilet. all services will be already available. only, do check on supply & drain pipes capacity as load is increased on the same pipes which were serving one toilet earlier..

I think a comfortable distance between the island and the counter is around 42". It seems that you have only 30" between your cook top and the counter. I might be a little too tight. The wall between the entrance and the kitchen could be 4' long instead of 6', you would then be able to move the island a foot which would give you more room between the cook top and the island. Could you switch the location of the toilet and vanity in your dad's bathroom so your enter facing a vanity instead of a toilet which is a lot nicer.

cool --but you can see the entire floor has been raised--do you have the ceiling height? a closet 'step up' would be less of a structural commitment, OR a buildup under builtin furniture--like bookcases flanking a fireplace, also some great ideas on HOUZZ i'd never have thought of. sorry i'm not tech-ie enough to paste the site:) of course if you go 'structural' --all walls and ceilings are fair game as well. remember that ease of access [or lack thereof] can affect stealth mode greatly--as in your pic: every time you step onto the 'box' in your pic you would hear a 'different' sound.

Since you have a focus light in that corner already, why don't you go for a big brass statue (goddess) or small brass statues on shelves or even indoor plants on shelves or brass bells on both sides with just statue in the center. Statue like the one below will give an aesthetic look. Wish you good luck.