Possible companions for such a class could be animals, a Nexu for example. And when you say it like that, all I could think about was HK-47, something along those lines.. The biggest problem I would see is customization, both in character creation and in-game equipment(but that can be fixed). Otherwise I like the idea~ Could have one melee and one ranged advanced classes, names for those ACs I will not try to think about.