Agree with Rolf. So many of the inexperienced hosts seemed totally lost and uncomfortable as they fumbled about. They never seemed to show personality or charm, and seemed to be there only for the paycheck. (Good example: David Sparks on The New Cross-Wits.) Rolf did fumble a lot (there's one anecdote of him looking at the wrong arrow on a Final Spin and being corrected by a contestant — on Teen Week, no less!), but he was one of the few "green" hosts who actually seemed to be trying. I mean, he was friendly with the contestants, he seemed to interact well with Vanna, and later episodes do show him developing a few mannerisms of his own.
Also, I think Roger Rose could've grown some as a TPIR announcer.