Maybe it's too expensive for some to bid on some of lesser known players. If you have a handful that don't get bid on, you can lump them into a group and sell them all to one bidder. Also, for the tournament, each time a player wins the tournament, you could move their handicap up. This is a good selling point to your lower ranked players, because they fell that you're trying to give them an opportunity to compete against the big guys.
Some people would rather have a chance at a break and run auction. You can add this and let it build up over time. You add say $500 to the pot and sell tickets to win a chance at the break and run, start off with $250 plus whatever is raised during the raffle. The winner tries to break and run a rack of 10 ball. Each ball gets he makes earns 1/10th of night's pot. If he runs the full rack, he wins the full pot, you've put $250 in the kitty to restart when someone runs a full rack. But, it probably won't happen often, and whatever is left, carries over to next week's purse. I've seen the purse bump up quickly and hit over 15,000. This is when the big dog's start coming from all around.