I wouldn't feel uncomfortable using a powder room placed where you suggest. It's not as if the door to the PR opens into the kitchen or DR. I'd go for all that storage and not give a second thought to the PR location. BUT.....this advice is coming from a person who has been likened to "trailer trash" by posters here because I have a toilet and sink in my laundry room. Despite the fact that the four of us living here are the only ones who use that toilet, that guests are directed down the hall to the proper bathroom, and that the door remains almost completely closed (can't close completely because...gasp...horror...the room also houses the litter box) during any type of large or small party, some here still think of me as trailer trash. Apparently, having a toilet in the laundry room breaks some sort of cardinal rule about which I have never once heard or read. Silly me thought converting the original laundry room, which took up the entire breakfast table wall with its huge, ugly, double bi-fold doors, to an actual room with a standard door around the corner near the back door would be better, more functional, prettier (gained a large wall in the breakfast area for art), and be less trailer trashy. We put a toilet and pedestal sink in because we garden extensively, and I have the world's smallest bladder. Having to take off all my dirty gardening clothes 22 times a day to tromp over light carpet through the whole house to get to the nearest bathroom wasn't practical. Nor did I enjoy having to get the carpet cleaner out every night after a long day outside to clean the dirt ground into the light carpet. Now, I sometimes put an old rug or towel down at the back door and can step right from the garage into the laundry room without having to remove all my dirty garments to get to the toilet. This decision was made even before having kids who like to play outside and need a bathroom. Yep, I'm trailer trash. And I'm not holding any type of bad feelings about being called that, am I? ;) Sorry for that rant. Keep the proposed PR and the storage.

In addition to the other good comments, I think you should also consider that this somewhat depends on the house and the neighborhood. In a modest house, vinyl or other sheet flooring is probably fine. It's most certainly economical to install. In a more upscale house, putting in anything other than ceramic tile is probably a mistake. We have a fair amount of tile in our house and we don't find the floors to be uncomfortable in the winter. To my thinking, both carpeting and wood of any kind (including laminates) are poor choices for a bathroom. Bathroom floors get wet, sometimes very wet. Using products put down in pieces that contain wood, or that would allow water to seep to the subfloor, will result in damage.

As a real estate appraiser I would advise to try to keep it. It will reduce the valuation by a few percent. If I were to appraise your home, I would now have to compare and adjust it from a 3 bathroom home to a 2.5. That's anywhere from $2,500 to $5,000 adjustment downwards. Understand that I don't know where you live or your real estate market. Even though there is no bedroom on the floor, it's a very usable space. At the very least, I'd put in a shower. You just never know when someone will lose their mobility. It looks like an older home. If your laundry room is in the basement, you may want to reconfigure it to bring the laundry up to the main living area. That would be an improvement in utility and the only reason why I would consider eliminating it. Hard to see everything, but you could reconfigure the doorway/entry and take over that vestibule area.

Concrete needs 'expansion joints'. Which means a massive slab on the wall is still going to have joints. On the floor the same issue will occur. Finished concrete surfaces are a lifestyle finish not a 'cheaper than tile' finish. Finishing concrete is expensive and it must be worked by a finishing concrete expert (more of an artist than a handy man). Concrete is porous. It is MORE POROUS than marble. I STAINS easier than marble. It ETCHES more than marble. Concrete as a 'finish' is considered a 'living finish'. It is always changing. It is always staining/etching. It is a whole lot of excitement to live with! If you love a surprise every single time you step into the shower or every time you make dinner or every time you step on the floor in bare feet then concrete is the finish for you. A HIGH END polished FINISH on concrete can be $7-$25/sf. The only thing that slows down the staining and etching (floors) is epoxy ($5/sf). A concrete counter top is stunning...and annoying...and surprising...It will show little spider cracks (as will all of the concrete surfaces). The finish on the counter top must be 'food grade' which makes it less resistant to things like water, orange juice, olive oil, red wine, white wine, etc. And you still need a better level concrete finisher. They can be hard to find. Ask yourself how much you want the imperfection of a living concrete surface? Can you handle the changes that you will notice on a weekly basis (if not daily...it depends on how much of a 'Type A Personality'.