1. I could try to hire a known supermodel and keep the role essentially the same. Invest in a name and try to cash in on established fame. The risk is the upfront cost.
2. I could hire a relatively unknown model on a long term contract with the goal of CREATING the next Vanna White who would walk the set for the next 40 years and be as much a part of the show as Vanna was. The risk is that it's hard to predict who can or will be great.
3. Temporary models. Bring in a constant string of new faces. Young, relatively inexperienced models are cheap. There's little to no commitment and if they aren't great, you get a new one next week. The risk is that the audience then only really gets to bond with the main host.
4. No models at all. Replace the walk and touch with screens being changed from behind the scenes. Replace the escort role with inconspicuous staff like Price is Right does. Again, the risk is that the bonding with the fans rests solely with the main host.