Considering you did say you want something small that you can flower in a small container, then a autoflowering plant or lowryder (in my opinion) is the way to go. A bit pricey for seeds, but if you get a good bit of them, you can have a hellacious crop!

Joint Doctors Lowryders


Link to some Lowryder/auto-flowering plants.......

P.S. Or maybe look into finding some clones, which can go directly into 12/12