[spiral]

I think variants of H/L stud with no qualifier and a declare are far and away the best. Put in the option to buy cards and escalate the betting toward the end of the hand.

Another devastating game that incorporates Mason's observation about how good draw is would be the following:

5 or 7 card draw, H/L with a declare, roll at the end.

The order of action would be:

get cards
bet
draw
bet
arrange your 5 card hand in a face down pile
everyone turns over one card
bet
repeat until each player has 4 up and one down
simultaneous declare for High, Low, or Scoop
bet
show

This game should yield a monumental edge against bad players