Potential host chapters apply to the state council about four years before a given convention. Generally, participant fees for tours, trips, and events only cover costs. A good chairman gets other people involved and lets them do their work. You can't do everything by yourself. And then No. 3, I think it's very worthwhile if the speaker has some renown so we can make good press out of it.
Variety is the spice of a convention program.
Some things win, and some things don't. I brought in an Elvis impersonator once, and that was not a big seller, but then we turned around and sold going to the race track to watch the dogs. As in real estate, location is everything in a convention. Having it under one roof, so participants can attend many events with little hassle, is also important. A successful convention is a lot of work, but the payoff is great.