Sounds like your view is the focal point. You might want to consider matching the curtains to the wall colour to lessen any "distractions".

I’d put my dining room in that space and turn your old dining room into an office and add some glass doors to your new office (old dining room). That way you can set up a dedicated space for your homeschooling. You don’t need two living rooms back to back. Put your piano against the stair wall where the guitars currently are. Put your dining room hutch on the 13’4” wall and hang the guitars on the other wall space (opposite the front windows). Hang your guitars so they are like artwork....big one in the middle and smaller ones on either side. Paint the chair rail white and all the wall space below the same white as well. This will help to blend your heaters. Paint above the chair rail a warm grey colour. Benjamin Moore Collingwood is one example and a google search will come up with other popular colors. One last suggestion is to get some full length curtains to frame those windows. Black and white check curtains will give that room a farmhouse feel. Black and White Curtains

BM Simply White for the warmer tones in the home. I have it on my walls and it's a nice neutral white, neither warm nor cool. if you want to enhance the cooler tones in the Bathroom, Try Oxford white, Decorators white, Chantilly Lace or SW Pure White. Since you are using 3000K lights (that's pretty dim) everything is going to have yellowish/pink tones. You don't want to use a white that leans very warm or yellow. Here is my room w/Simply White on the wall and the trim (one in eggshell the other in semi gloss). Window faces south/west my table lamp light is about 3000K or so, and you can see the warmer hue it gives to the wall. In this pic my ceiling light is 4000K. You can see the diff between the two light sources and what it does to the paint color. The white w/this lighting looks a lot crisper, but still not overly blue or cool. Do not use White Dove. I tired that first in this room. horrible

contact conifer kingdom. and have them recommend some z5 JMs ... they sent me a few.. and they have thrived in my cold z5 ... i dont recall the names now ... they have an extensive JM selection: https://www.coniferkingdom.com/ https://www.coniferkingdom.com/our-plants/maples/ trust me and embo.. the most exciting and exotic ones are not z5 compatible.. so dont get to excited about the possibilities .. and you should be well aware ... trees NEVER stop growing at some magical height ... its all about the annual growth rate.. and how long it takes to 5 feet.. and then double that to 10 feet ... the rub is.. if you find one that grows lets say one inch per year.. it will stay small .. but we will all be dead before it hits 5 feet ... eh ... its the old catch 22.. to fast to height.. and then it wont stop ... and though you may find some min conifers that grow an inch a year.. you are not going to find a maple that grows that slow ... at best... if you can find one.. zone appropriate that grows 6 inches a year.. you would have at least 10 years to your height limit .. and then you can keep it smaller by proper pruning.. lets call it in ground bonsai ... but obviously dont go for anything with a one foot or more growth rate .... unless you have a big stick to beat it back with ... btw.. many JMs have a very fibrous root mass.. and its hard to grow anything.. like hosta.. under them.. as they are water hogs ... im sure youve heard.. maples kill hosta thru water competition.. JMs are no different ... ken