If going up and down stairs frequently isn't an issue for you, then do it. For me, personally, I'd rather go up and down a full flight of stairs a couple of times per day rather than go up and down a fewer number of steps 30 times per day. I have family members that own a 4-level house. They make it work but ugh, I could never do it. When you enter you're on the main floor which is also the 2nd level. This level has the family room, powder room, laundry room, and garage. If you walk up 3 steps you get to the formal living, kitchen, and tiny dining nook. From this 3rd level you then go up about 10 steps to get to the bedrooms and guest bath. Then there's a basement which has around 8 steps maybe. Constantly going up and down stairs all day long, even if it's just a few at a time. It also really breaks their house up and my sister-in-law has commented that it's difficult having a lot of people over because they have to spread out on different levels to fit comfortably.

well..neutrals can be deeper too. neutral doesn't mean "light"..it just means a color that will most likely be a background that most people would find natural to be a background color. Even though a lot of colors can be easily considered neutrals, since they're so prevalent in nature...say some blues or greens..If it's something you see a lot outside, and I mean a lot-don't worry you'll perceive it as neutral. If beige is neutral-then brown is a neutral too..technically it's a much darker beige, as far as i understand..or should I say-beige is much much lighter brown lol they all are colors. and some neutrals are very capricious actually. take white for example-it is a perfect background but it needs light to become perfect background..and it will accentuate a lot of things. which you sometimes want to accentuate, if you have great architecture for example..and sometimes you don't. if you have a dark bland small room-white won't do it any favors. of course one should remember there are many whites..) in short, no, deeper colors won't necessarily make a place small. they won't make it big either lol. they can make it livelier though..cozier. you usually don't want to go really dark in a big space, not because it will make it smaller, but because it might change your feel..too much dark might feel oppressing. but just a tad deeper color and real dark color are two different things. you know what you're ready to commit to..took me some years to go more colorful, and I do prefer muted colors so it still reads pretty soft. neutrals can be as deep and amazing as anything else..when you'll start getting samples, trying them in your unique space and light- you'll see what you are comfortable with. and what makes the given room lovelier to you. just don't believe the names paint companies give-these are very deceiving..:) if you're looking for a color, especially a neutral one-just look everywhere. looking for gray? great. check the whites too:) etcetera blue sectional sounds very cool. colorful furniture usually works well with neutrals allover the range. and colors too lol. put it in a gray room-it will work. or in a beige room-and it will work. or in a white room-still will work. or take a "real" color-still will work, in most of cases. i don't find your paneling that horrible btw-but maybe it's because i don't see it up close. quality of wood matters a lot of course. sorry for the ramblings..i get like that sometimes lol

I would not tack on some kind of modern glass and metal nor cable rails. This house is from the 1970s. Lean into that and don't try to make it something its not. Unless you use the deck a lot, I would remove it altogether and put a nice picture window in instead of the doors. If you use it, make it into a balcony with some nice bistro seating. Remove the stairs, put in some simple french doors, replace the rails with a simple metal design that is period appropriate and will blend with the rest of the house. Get some simple planter boxes and fill them with some nice annuals. I am seeing some red or warm colors. I also like the idea of a breezeway, pergola or some kind of covered walkway. Check out some of the MCM mass built houses in Palm Springs for inspiration. There are a lot of covered entrances to keep the hot desert sun off your head on the way into the house. Agree that the yard needs some landscaping help. Agree with some sculpted evergreens, Houses will tell you what they want to be. This is a loud, proud split level. Don't make the mistake that so many do and try to make the house conform to some trend or modern ideal. Let the vernacular of the house speak and enhance it with appropriate updates or restorations. I actually kind of like the quirky nature of this house.

I agree with @calidesign about the bathrooms. If you close up the door on the right of the master bath and convert the other one to a pocket door, you would have space for a nice, large shower, a double vanity and possibly a little extra storage space. For a guest/downstairs bathroom, I would remove the small closet from the 2nd bedroom (there's already a large walk-in in there) and bathroom door, and convert the doorway near the bottom of the stairs to a pocket door. By removing one of the doors and absorbing the closet space into the bathroom, you will have a more spacious bathroom with storage and room for a larger vanity with counter space. I don't think it's worth sacrificing kitchen space or master bedroom space to put in a guest bathroom upstairs, unless you have guests over a lot (in which case you could create a small bathroom on the left side of your kitchen, but you will lose valuable real estate). I honestly don't see anywhere else it could go upstairs without putting in obtrusive walls in your living room. You could narrow the foyer but because your ceiling are so high, I think it would end up costing a lot for just a small bathroom. Also, it would throw off the symmetry of your house quite a bit (looking at the entrance from the open space, one side would be open and the other closed off; the window would be off-center).