Shimakaze:
Well, in V&V there's already a mechanic to help out the player who rolls only a few powers. Pg. 4, last paragraph: "A character with few powers tends to be less powerful than a character with many. This being the case, the GM is encouraged to upgrade the usefulness of the powers received by a character with few powers, in order to make him capable of contending with more powerful characters."
I always do this. I think if you have only 1 power, it's re-roll time. But if you have 2 powers, then I (if I'm GM'ing) will treat that character as if they have both powers at 2x, or one power at 3x, more or less.
You can make some awesome characters like this. But, some really weak powers can't really be enhanced too well, so I work with characters.
You can also get some sweet heroes with just 1 or 2 powers, like a 'power copy' absorb power (had that in MoSqUiTo -- but he also had Super Speed -- super combo!), or enhancing the 'transformation' power to copy the thing *perfectly* in all aspects, including memories (Rogue?).
Last point -- when I roll a weak sauce character, it's a bummer. I admit it. Every hero needs some flair!!!