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.

One option, I would get a very large rug so that all the chair legs and at least one corner of the sofa is on the rug. I think I would also bring the table set away from the window a little more. I think there is enough space to place the two-seater opposite the table in front of the window. or bring the table forward toward the kitchen ....... With the sofa centered to the large window. They probably will not be opposite each other, but at an angle which is still ok. They might seem more functional for the table set to be closer to the kitchen. Another option is two rugs in wide runners. Creating a walkway through the center of the room. Still thinking the sofa center of the right window. Just some ideas :-)

I agree with divadeva. More lights. If you can add pot lights do it. If they're already there add task lighting and up the wattage on the bulbs on the pot lights (replace with LED and you can make them brighter because the wattage on LED is lower for brighter light). If you have all of that add decorative lighting. If ventilation is an issue find a way to move the air around or add air filtration. Maybe the HVAC is deficient. Maybe you can add a HEPA filter instead of the standard one that comes with the unit. Call an HVAC specialist to see if there is a way to boost air flow in the room.

Tsilanko, I would always recommend professional installation where needed. But what I am doing here is suggesting that WHEN you are planning to build or renovate, to consider how your plans will affect you in 20 or 30 years time. Split levels are very hep when you are young. A kitchen 3 steps down at 30 is rarely a problem, but might be a hazard at 60, or, as Marjie1059 suggested, if you break a leg. ... All my parents' homes were terrible for old people. They were forced to move to a bungalow in extreme old sge because the location and design of their home was more suitable for an active young couple with a large family than for an elderly couple with stroke disabilities. I would not want to move again, so my present home has features built in that make ageing in place simpler. Mostly small changes, like grab rails, and lever handles on doors and faucets. A major disability suddenly suffered requires major changes if permanent. I did look at this because it came up in the discussion, but if you look at the heading, Planning for Disability, it means just that. Plan ahead so you don't have to make expensive changes later on. But thank you for your advice, yes, major changes are not in the DIY domain.