Just to clarify, you have presented 3 versions. I believe the consensus is the original version with the wood grain ( linen grain) cabinetry works the best and is most updated. The only thing that is out of place are the cabinets or "shelves" on both sides of the range hood. If this is what you need to find a solution too. I would suggest only experimenting with rendering options for these two cabinets( or shelves). This cabinet ties in all the other hard surfaces. The white is not working. It just adds another element. The black is a little dated.

A houzz contributor, not too long ago, had made a wine rack out of 4'x4' wooden pallets, that are used in the US to move a load of goods with a fork-lift truck. Perhaps they have them in your country. He cut them in half so they were only two feet deep and stacked them up to high counter height. The wood would be a nice contrast with your concrete, might add a little warmth to the space. cascio.offsite@gmail.com

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.

I think this piece is quite lovely. It appears that your couch and chairs have dark wood so I would be tempted to stain or paint the buffet to match these items. Changing the large modern handles to smaller antique ones might help to make it less bulky looking and tie in with the other items in your room.. I like the idea of putting a mirror in the upper door, however much as I like the criss cross effect in the sample pictures, adding more detail may conflict with the curves in your sofa and chairs. You could look for a decorative detail that has more subtle style. As for placement, it might go on the short wall where you have a bench or even on the wall where you have your table with two chairs, one on each side to balance the look.