Lots of ideas....couldn't resist adding my two cents. i copied your photos and did a little cut and paste- it's messy, but hopefully gets the main idea across. i'd put your sofa in front of the large book case, chair by the fireplace, tv on the stand on the wall opposite the fireplace - so you can either look at the fire or the tv. Someone suggested using frames of one color for your photos - an inexpensive way to do that would be to spray paint them all a dark color-black goes with everything. Since your shelves are a medium tone wood, display things that are dark or light so that they contrast against the wood. Limiting your display items pallette to a few values usually helps to unify things. (I think that's why so many people want to paint the shelves or put inserts in the back to help your nice things read more clearly...some get lost). If you want to "splurge" -you may consider having a carpenter make a few solid tall cabinet doors to provide a visual break in the shelving. I'm showing 3 doors - 1 on the right side of the fireplace and 2 on the left to leave two open vertical shelves for display on each side - with things arranged to frame the fireplace as the focal point. To add some height to your big vases, consider stacking some books beneath them. Enjoy experimenting untill you get something you're happy with - good luck!

DO NOT USE DRUNK TANK PINK FOR A ROOM! Sorry, Groveraxle, but further down in the site you linked to it said, "Prisoners did respond and calmed down, as hoped, initially. Major goof: If they hung around too long, they became even more violent." Some police depts. have a pink room, but are cautioned not to let anyone remain in it more than 1 hour. It's called the rebound effect. I read about this while working for a state police agency.

I must say I find the tall ones , a bit disproportionate to the rest , try it with one third off, (the top sheets) and lets see . I would then align the middle tall one(now reduced) to the bottom of the one next to it ,then I would also reduce the distance between all the frames to about 4" in between. Even if the display is not the whole length of the stairs, as long as the distance at the bottom of the stairs is the same as the distance at the top of the stairs, it will work,

About your plumber saying "plumb layout is confirmed". That is a load of rubbish. It's fairly easy to move drains around (yes he might have to rip up some walls, but he can also do off-the-wall installations to avoid that). In a small bath proper placement is of the utmost importance!!! If you have the bathtub and shower next to each other that will be much better and then the glass separator idea should work. padmaramachandran's (see post above) setup sounds more reasonable to me as well (see first picture below). This is similar to your setup but as you have more space you could put in bath tub and shower where the picture only shows a bath tub. Also if you do it that way you could theoretically have a bidet or a wider wash basin (small double perhaps too). Example layout: Do you need a bathtub in the guest bath? If not you have a lot more room to work with. E.g. for a double wash basin and large walking shower and a bidet (2nd picture). Example of off-the-wall installation for toilet and bidet and a large walking shower. Finally if you ignore this advice and do it the way you planned ;) then I suggest you really thing about that glass separator. Doing it right will make a lot of difference (see 3rd picture). Good luck!