IMO I would first solve the function issues you have outlined and then address the style issues you have requested. As with every design problem there may be compromises to get most of what you've listed, but function shouldn't be one of them. I've attached a layout and some examples of furnishings & unique equipment that may accommodate many of your requests. Please carefully think about keeping a frankly huge armoire, that you still have to spend time and money to refinish, to hold a printer that could reasonably fit on a small shelf. The printers seem to get smaller everyday as do the computers/laptops. How many of us got stuck with armoires to hold huge TVs? The local Goodwill where I live won't even take armoires anymore because no one wants them in their homes. That item in particular, from my perspective as a designer, is like fitting a square peg in a round hole. I often look to the RV industry to provide me with clever equipment that does double duty, like hidden work surfaces that can pull out of standard cabinets when needed, and slide away when not in use. I think you can assemble a workable room, with the special style you're looking for & even that special settee, but I would build in files and storage which is always needed, find a clever way to close away your DH clutter so you don't have to nag, & look for high tech items to help you reach you goals. Built in wall units are not inexpensive, but everything doesn't need to be custom. Cabinets from any modular kitchen cabinet manufacturer, even IKEA, could be used to assemble your workstations. Good Luck

I agree with the location of the dog shower being suboptimal. It's in the front of the house and near the clothes / coats. Where will you store the shampoo and the towles required to dry them off? What about the hair that gets produced in the washing and rub down process - how much of that ends up on the clothes? and the humidity - you need a fan in there. It's way more normal to have a functional laundry room with a sink/ shower, etc. You will now be carrying dirty / hairy dog towels through the foyer kitchen, master bedroom and bathroom to get to the washer. (honestly at this point it might be cleaner to bring the dogs into your master shower! I do that sometimes!) I totally get wanting to have a dog shower (have one) I totally don't get having it where it is and so far away from where the accompanying items need to go / end up. I would also rethink the master sinks. No space that is usable for any kind of normal bathroom grooming. And dead space behind them. Depending on how deep that is, finding counter material could be challenging as well! I don't have an issue with your master shower - mine will be 7x5. I do think you should have 2 shower heads in that space. Make sure you work with the bank (assuming you are getting a construction loan) on a 2 bedroom house. Not sure about your area, but they are hard to finance here, and I expect would be even harder with a self build. Trying to do a self build with a bank is tricky - make sure you have that nailed down. If you are paying 100% out of pocket - then never mind! (and good for you!) You need a interior designer for this if you are this far along with the plans - you should be able to find someone who simply works by the hour.

Pictures of your kitchen and nook would help, but I think using lighter tones of some of the colors in your kitchen or going neutral would look nice. You can add some modern elements with other decor and keep things minimal using clean, simple lines. This photo shows how you can use a bit of wood to match the kitchen and then use a lot of white or off-white. Using less ornate light fixtures and shinier metallics can add a touch of the modern. Keeping the room a bit rustic but adding modern touches with a chair, lamp and artwork can offer a more seamless transition. If you want color, I would opt for softer neutrals. Then add some fun unexpected modern pieces.

Maybe in a weekend cabin? I'm not sure, I'd like to see the entire space, more photos. What comes to mind though is lack of ease in cleaning. I see surfaces that could collect dust, spray products that don't really appear 'wipeable'...