The forward penthouse cabins on deck 9 are fantastic. Large main cabin, full bath and separate partition for the toilet. Good storage space and large closet for your clothes. The corridor from the sleeping area to the bath is pretty narrow, meaning you've got to be pretty careful heading through to avoid hitting the drawer pulls.
Also, there's only one US-standard 120 volt outlet, which is near the mirror outside the bathroom. There are a bunch of 220 volt outlets (designed for plugs with two round pins.) If you've got a lot of electronics to charge, consider bringing the appropriate adapters.