Brock, for sure. I always thought Brock was more suitable to hang out with because he's much more mature. He's obsessively weird around girls but that's still more natural than Cilan, who is just plain unrealistically weird about random things for no reason. I understand the need for humor in Pokemon and I like that, but it can be overdone. Even though Team Rocket can be stupid and funny, their role on the show justifies it. It feels like putting too much humor in a main traveling companion is out of place. It makes Pokemon more like just a regular cartoon than a good, epic anime with a few laughs. I'm fine with giving Brock a break every once in a while, but they better have him back for the next generation!