Caleb is all over the place, constantly. I always incorporate him in the households I'm playing, either as a spouse or a roomie. He absolutely LOVE painting. When he's done with something I told him to do, if I'm not quick enough, he will race to the nearest easel. I don't mind, he creates new things he can admire, so keeps him happy. And he's making tons of money with it too, because he maxes out his skill very quick (large, abstract masterpieces are apparently the huge sellers).
I don't really see him making drinks that much, and I'll allow all my sims to do it (grabbing water is no issue in my houses, I never ever have sinks in any of them) They'll either drink them or I put them in the fridge for later. All my played houses have fully fitted home gyms, so they are absolutely going to work all those calories off :) Same with food, really. In my current save, he's just entered the culinary career for the first time (usually I put him in painter). This will be interesting.
I find Caleb to be an easy sim to care for, and he's one of my top 5 premade sims to play.