You're welcome! If your tile person is as much of a perfectionist as ours is, ask him (or her!) to let you know (once the tiling begins) if your niche(s) needs to move up or down at all in order to allow for full tiles at the corners or elsewhere. We could have allowed our tile guy to close up at least one of our niches by up to a half or full inch, but DH "sucked it up" and "moved" the niche up by that am't because we didn't want to close up the niches at all (he chiseled out either the floor or top pieces or both of cement board in the niche, screwed in new pieces, spackled it with whatever he used for the tub surrounds, and then applied three coats of Hydroban, all in the middle of the night, so it would be ready for the tile guy first thing in the morning!). PITA at the time, but worth the effort in the end, because the niche and its surrounding tile work appear seamless; neat and perfect. :) As for the vents/fans, they work really well. I had noticed the one in the MB seemed much noisier than the one in the hall bathroom awhile back, and then it had stopped removing moisture/condensation (and bathroom smells) well. Apparently where we had vented the fans to the outside wasn't ideal, nor were the vent/duct "covers"--they clogged with debris, so the fans couldn't work efficiently. DH rigged up a temporary solution (he will relocate where the vent fans duct/terminate once the cooler weather sticks around), and what a difference. Quiet fan(s), and totally clear mirrors upon stepping out of a steamy shower! Not to mention fresh-smelling bathrooms after use, too!!!

See below.

We only have space for a very small window, but it beats no natural light at all. Ours will be very small and clear glass because there's no way anyone is seeing into it, but for the other bathrooms that don't have so much privacy I'm going to use an obscure glass similar to the "Minster" pattern in the link. I wish I could fit a full-sized window, I would go with clear glass and sheers. To be honest, I could find happiness in just about anything that wasn't glass block. Sometimes I feel like the only person alive who can't stand that stuff. Makes me feel all Miami Vice-ish, like I need to don a white silk pant suit and peach cami. I tend to think it doesn't get more timeless than "plain old glass". You can always apply a treatment or film if you want something different without the commitment. Here is a link that might be useful:

There are no hard and fast rules for tile orientation. You can run them whichever way looks best to you. My daughter and my son both recently redid their bathrooms and put 12x24 tiles stacked vertically on the walls. They didn't have to decide on vertical vs horizontal for the floor because they used 24x24 squares on the floor. In my bath I have 10x13 vertical on the walls and 18x18 on the diagonal on the floor. IMO the large square tiles make their small floor spaces look bigger. Do your tiles come in squares too? Maybe you could put them on the floor. If you stay with the 12x24s on the floor placing then horizontal ( long side parallel to the tub may make your room look wider). You can still put the wall tiles whichever way you want. Here's a couple shots of my DD's tiles Good luck in your remodel.