Perfectly acceptable, as long as it is a 15 amp circuit. (You'd need 12/3 on a 20 amp circuit.) I'd also clip off the neutral lead where it enters the junction boxes.

Wouldn't be a bad idea to just cap the white without cutting it in case you would like a fancy switch that needs a neutral.

You can also get a switch/receptacle combo if an extra receptacle would come in handy.

I would never clip off the white or any other unused wire. Just roll it up in the back of the box. You might need it in the future for example if you installed a fan with a light. Then you could switch both of them separately.

I absolutely hate it when "the last guy" cut off an unused wire, because it never fails that whatever I'm doing would be ten times easier if that wire were available.

I'm with hendricus and joed: cap off the wire, fold it up in the back of the box. Someday, somebody will thank you.

You can also use 14/3 for TWO switch loops, so a use that immediately comes to mind is a future change to two switches for a light/fan combo with individual control.

Being a bathroom, is this going on the dedicated "bathroom" circuit, or another unrelated circuit?
Someone suggested adding an extra receptacle-
This would need to be on the bathroom circuit, not an any circuit that was close by and available!

I personally am against putting receptacles and lighting on the same circuit anyway :)