Chris Warren is a great field reporter. He seems to bring a lot of fun with his live shots. 
He is decent in the field. A lot more character than when in the studio
That's probably because of all the adrenaline live reporters get when they're out in the field. Especially in cases of severe weather.
As for him being "shy" in studio, that'll go away when he gets more in tune with everyone else's on-air personality. I know he's been at TWC for a few months now, but he's only just started working (mainly) on Weather Center. He'll get a better feel for what the "tempo" is like.
At least that's how I feel when I produce newscasts. I'm more shy and reserved when I start out at a new place, trying to get a feel for what everyone's like and what direction the show is going in. Once that happens, I become more confident in myself and I step out of my shell and try new things. I think that'll happen for him. (Just my opinion, lol!)
ETA: I actually think he's very good.
