Well, let's see...
Bounce:
won't work if you don't bounce Braids herself (or himself?), and that would mean you have to pay 2BB each turn. No, no abuse possible.
Squirrel Nest:
Good idea, would work nice. I'm just trying to think of a G/B squirrel deck - nice: "the deck of the undead squirrels". It's very scarry, isn't it ;-)
Penumbra Guys:
Hmmmmmmmmmmmmmm. Could be interesting. Play a Penumbra Bobcat, play Braids. Next turn, sac the Bobcat, get the token, play Haunted crossroads. Pay B, put Penumbra Bobcat on top of your library. Play Bobcat. Repeat for a lot of tokens. Add some card drawers (Archivist usw.) and make your opponent mad; he won't like cats anymore.
However, the idea with Squirrel Nest would work better.
And for mono-black (non-T2) use Breeding Pit!