Guest bathroom reno ideas

Our current house project is moulding - baseboards and door casings. We'll probably take a moulding break after that, putting off crown moulding for a while, and tackle either the guest bathroom or the kitchen. Since we have a walk-in shower in our master bath, the guest bath is the only place I can retreat to for a nice bath. I've only done this 1 or 2 times in the nearly 3 years we've lived in this house. It's just not inviting, but there is potential! My only "must have" is a tub with some type of jets.
I'd like a spa feel in the bathroom. One day, this will be the kids bathroom, so we've got to keep that in mind too. I like slate and stone work, maybe we'll save that for the master bath. I like how the slate in this bathroom matches the wood tones and keeps it all light. I prefer larger 12x12 min. or 18x18 size tiles for the walls - makes it less busy to my eye.

But these just speak spa to me - neautral, clean, crisp. The second is the Hyatt Regency Ft Lauderdale and the third is the Hilton in the Chicago O'Hare Airport. Most of the designs I see that I like are by Hilton hotels!

I love love love glass moasic tile. But may save that for the backsplash in the kitchen and just use larger tiles or stone work for the bathrooms, adding small glass moasic accents like mirror. These blue moasic bathrooms are beautiful, but just not the sophisitcated, spa look that I'm going for. I know this is a guest/kids bathroom, but simple, clean lined bathroom can always be made kid friendly with some color accent items. These 2 are from the Solamar hotel in San Diego. It's got just enough glass moasic accents, but may be a little too 'beachy' for our bathroom.