You can also attach a piece of hardwood into the studs at the outer edge of the wall and hang your hooks onto that. We did that for our entryway knowing that all the kids' heavy backpacks would be hung there. We painted it in contrasting color.

It is wide enough, fortunately. If I were to put artwork or a mirror above it, is there a general rule for how big/wide that art or mirror should be?

sheesh, we're supposed to picture all of this? just put the towels where they are comfortable to use and look good to you. there is no standard rulebook for towel bars. what's good for a person of 5' won't work for a person who is 6'5".

I've had hooks for a few years and really prefer them over a rail -- takes up minimal space for the quantity of towels, towel's are easier to hang, they dry better, and I actually like the look :) I always give a guest a clean towel and then the hook is simply so that it can dry afterwards. That's never been an issue for me :P My regular guests already know which hook is "theirs" haha! I closed the end of the tub/shower because I didn't want water droplets getting on my toilet area and also because I didn't want the shower to be too drafty. You can't see it from the floorplan, but there's a 24" high niche in the 2x6 wall running the entire length of the room that provides more than enough space for shampoo bottles and some towel shelves :) At this point I'm settled on the towel hooks, but just need to determine the ideal quantity and placements :)