Piecemealing the Bathroom: Tile and More

Recognize this sexy light? Yes, I think it was in my grandmother's kitchen too. Well, in the face of great adversity (or the lack of matching lighting) we have decided to do it up really old school and go with this light for the ceiling in the bathroom. It's certainly retro. It's chrome. And, you know what else? It's cheap! $20, baby. Which means, if we hate it, it's not the end of the world. I think it will go with the other lights pretty well. And, that's right, it's only $20.
After doing the bills this morning I found we had a few extra dollars left so I went ahead and ordered our accent tile for the bathroom and then made a trip to Lowe's for the extra white subway tile. We plan to do something somewhat similar to what we did for the kitchen backsplash but instead of interspersing glass tiles throughout we will do one stripe all the way across, probably about two-thirds of the way up. We had a bunch of the subway tiles left anyway so this will look nice, we think.

While at Lowe's I investigated backerboard for the tub surround area and came across this stuff by Georgia-Pacific called DensShield. It looks lighter and easier to cut and you don't need a vapor barrier. I think this is how we'll go, when we're ready.

I also thought a bit more about the lighting situation. The vanity lights that are currently there are the light/outlet combo type; obviously not to code. I thought, no problem, I'll just slap up a new electrical box under each light and we'll install GFCIs. I'm wondering though if it's actually more complicated than that and if this is a job for an electrician. I read something online that said we'd need a new breaker. Ick. What do y'all think?