Sure charter lotteries are a gamble, but so what? You either get in, decide to go Out of Bounds somewhere, or go to private school. I know of exactly 1 person who was shut out of all the different lotteries. The following year for K they got into 3 schools! Every one else (and I'm literally talking about my entire circle of friends, extended friends, and neighbors) in my East of the Park neighborhood, got in somewhere that they are happy with. The odds are not as grim as some people would paint them.
But a lot of these schools are middling at best. I'm sure of it. Still, that will suffice for some people. Some people prioritize X or Y over a school that is 'fine.' OP just needs to decide if she is one of those people beFORE she sinks a down payment into a home.