You have two of mine already: Billy and Eoin.
I'm a Tony Horton fan. He's encouraging, funny, no-nonsense (in the workouts, that is, not the chatter) but not too hardassed.
There are several in yoga:
Rodney Yee. His alignment instructions are fabulous and some of his sequences are genius. Besides the obvious.
Erich Schiffman. No eye candy here, but a great soothing voice, spirituality, and wonderful yoga.
Nirvair Singh. Like Erich Schiffman for kundalini.
Bryan Kest. Love him or hate him ... I only have his original series (keep hearing that's the best), but I've also taken a live workshop. I love his attitude and his bluntness. Some don't.
And he looks good with or without the hair.