Canderous as a joinable NPC? Nah. Canderous as a tough "boss" type fight? Heck yeah.
Let the old war dog finally go out in a blaze of glory.
please note: A suitable alternative for the player not getting to fight Canderous would be a cameo in which the old mandalorian comes out of who-cares-where to lay the smack down on that Atton Rand chump, preferably by bludgeoning his head in with T3