Beach cruisers, roadsters, and related bikes.

I bought a cheap Wal-Mart aluminum frame cruiser for $150 three years ago and it held up surprisingly well. Mine looks like this, minus lights and fenders. It is a nice bike for trail and off-road use.

Do you anons think cruisers should be single speed, 3 speed hub, or have a full cassette derailleur? Do you think a coaster brake is good enough? I like the traditional single speed coaster setup.