one key question is this:

how easily is your BR replaced?

if it's easy to replace, then go for it. if not, then i would stick to $100 tables or less ($50s seem about right). if you're doing it for fun, there's no hurry to move up. also, i'd recommend bonus whoring for an express route to building the BR.

as for building your bank account, i'd recommend getting a sufficient BR for the game you want to play and can beat, and then taking a certain percentage out for you and add the rest to the BR (for the inevitable downswing and/or moving up in stakes). only you know what the right numbers are.

na.. bankroll should be bigger for 6 max. The swings I have are huge. I'm losing and winning 2-4 buyins a session at 2/4. $1000 is not gonna cover 1/2. $1000 is enough for a shot at 1/2...not a bankroll IMO.