Your conference can be a profit center even if you have an exhibit focused show. Raise your conference fee to $1000+ by making the educational component of your show vital to the success of that segment your attendees who will pay for vital knowledge (e.g. CFO yes, bookkeeper no). Even at only 200 conference attendees, you can generate $100,000+ in profits.
Use speakers who actually do what they lecture on; DO NOT use your exhibitors as speakers on the paid program—unless they are on a panel with their competitors. Create an advisory board of experts on the various subjects covered by the show. Ask them what the "hot button" topics are and who is the best speaker for each. Always include some controversial and timely topics such as "why the Internet will put widget distributors out of business - and what you can do about it."
Invest enough to adequately promote the conference—one show spends $160 on promotion for each conference attendee. Get the prospect's attention by writing salesy session titles and benefit copy ("you will learn…"). More on conference marketing in future Tips.