Ahh...green Extended (maybe even Type I) beatdown...how nostalgic...
Uh, OK, anyway, I don't know how big a mana engine you want, but with the run of the mana-producing elves in Magic, those that stand out are:
Llanowar Elves
Fyndhorn Elves
Priest of Titania
Quirion Ranger
Rofellos, Llanowar Emissary
You could also use Eladamri's Vineyard, Gaea's Cradle, Heart Warden, etc. As much as you would be risking by playing all elves, I think a deck with that kind of mana production has to be faster than most decks' defense mechanisms.
Elvish Fury fits the theme and is common, and Overrun is an excellent finisher, but with a lot of mana, maybe Vitalizing Wind would work? I know that it doesn't grant your creatures trample like Overrun, but maybe you could include Stampede Driver.
I personally would go with the Snake Basket, too, but if you want to stay in theme, maybe Collective Unconscious would do to replenish your hand and allow you to cast more creatures. I have a mana-engine deck that relies on Collective Unconscious to refill my hand and allow me to play more mana engine cards, and it's quite effective.
Your deck should be extremely fast, and only truly dedicated decks should have a chance against that kind of speed.