Gray IS neutral, as are beige based and off white colors. Why invest in "trends"? Invest in a more timeless color that is not subject to fashions trends. That is sound advice when building a wardrobe or adding elements to your home. Who cares what "NO ONE" wants? The real question is to ask what it is that YOU want? "NO ONE" does not live there....you do. You cannot go wrong with a neutral and non dictating base color. You can always add accent colors. Those should be the trendy colors---the accent colors. They are usually the things that are more easily changed out. This kitchen needs more that just a change of color for the cabinets, though. It is almost a moot point. I agree that painting them is not always a good choice. I had painted some cabinets in my kitchen at one time. Once you opened the cabinet door, you saw that it was really an old cabinet. Unless you are going to go behind the doors and renew that space as well, you might as well not waste your money and time. They almost never look good. I have seen some that do. But, most times it is not a good look. Besides, the finishes on a new cabinet door are finishes that I could never attain from using ordinary paint. And, to get such a resistant and smooth factory finish as what is on my KitchenMaid cabinets would require materials and tools and techniques that are not readily available to me, the DIY person. One advantage for you is that your doors are a slab door and are easier to work with. The two colors that you chose are beautiful. It looks like what ever is on your floor has a gray tone to it.

If you are planning on renting it out I am not sure I would invest in hardwood unless you are renting high end luxury units. I would talk to a local property management company and see what they recommend for rentals in your area and read a dozen articles on rental forums (not articles written by companies selling flooring). Tile is a good, durable choice. If you are in an area where it is warm year round tile could be a good choice throughout. If it is a 4 season climate tile is a bit too cold for many in the winter seasons. I am a bit surprised that the counters are granite. Usually with granite you don't have the completely squared edge profile and most people use a full backsplash vs the 4" bottom splash. I am kind of sorry to hear this because it is dark, drab and not the best color for with your cabinets. I would price some options for replacing the counter. Does not need to be granite. Can be quartz. For a rental you will want something durable or something inexpensive to replace.

Balboa Mist is a great color. I would pull from that and select a nice green to go with your wood flooring. Don't rule out Benjamin Moore. They have some fabulous greens that you can get made up in INSL-X Cabinet Coat (do semi-gloss which isn't that glossy and more durable than matte). INSL-X will be waterborne and won't yellow over time like oil-based paint will. The trends in cabinetry are moving away from grays, and gray doesn't fit in with your wall or flooring color very well. If you go dark enough with a green, it will verge on a dark neutral tone that fades to the background and will work with your marble look-alike counters. Backsplash tile should be chosen last after everything else is settled.

You could do it w/a jigsaw. (borrow or rent one if you don't have one) These are some DIY links that will walk you through it. Grab a friend w/a bit more know-how if you don't think you can manage. (or, you can always pay a pro to do it. ) DIY all you have to do is go to a glass shop and give them the measurements of the cut piece you'll need. try seeded glass. then you silicone the glass on the back and hold in place w/glass clips. https://www.familyhandyman.com/project/convert-wood-cabinet-doors-to-glass/ a few more how-to's https://www.confessionsofaserialdiyer.com/how-to-add-glass-to-cabinet-doors/ https://providenthomedesign.com/2014/03/03/diy-glass-cabinet-door/ This one is very detailed: https://simplyrooms.wordpress.com/2012/09/23/project-converting-cabinet-doors-to-glass/ you may need some more tools for this since you are keeping the real wood. you'll have to finish off the edges after cutting. not difficult, just another step. for a few hundrend, you could prob get a cabinet guy to do it all for you.