I've been looking for a nice outfit for Raul, and after finding one I realised he won't wear clothing because it has less DT than his default outfit. I'm on PS3, so is there any way to get a companion to wear something like this without console commands and such?

Don't think so. If his default outfit doesn't show up in his inventory , it's probably not possible to take it away from him.

Cass looks kinda hot in Raider Painspike and demolition armor. In FO 3 I had my ghoul in metal armor, he looked mean in that.