Optimum Strategy in Home Tourney

[JC21]

I've recently started playing in a small weekly NL Hold'em tournament. It's a $10 dollar buy-in, with around 10 players (it ranges from 9 to 12 players). Basically, we each start with 40 chips, with blinds at 1/2. Blinds raise everytime two players are eliminated, and every 15 minutes heads up. 2nd place wins $10, 1st place wins everything else (ie, with 10 players, 1st place wins $90). What is the optimal strategy in this kind of tourney?

The chip structure is set so that there's not much room for aggression. I am a fairly tight player, but with such small stacks, I have difficulty determining when to charge, or to risk committing to a pot. The other players aren't horrible, but they are certainly not great (there is only one other player who has actually studied up on poker). How should I adjust my style, especially early in the game? How about when I'm heads up (given the payouts)?