Hobgoblin Khan
If for nothing else, you need one of these guys for each of your Hobgoblin Wolf Riders units. They have the Levies and Warband USR so, given enough ranks, boost the LD of your Hobgoblin Cutthroats to a nice 10. They have a decent hero statline and can take all the equipment they need to work well with Cutthroats, Sneaky Gits and Wolf Riders. Be aware that his lack of certain special rules might interfere with those units though.
Especially on a Giant Wolf a Hobgoblin Khan can be a nuissance for your enemy even on it’s own. He also has access to 50pts worth of magic items, which is a lot for this guy. He’s cheap on his own and chances are your army is going to include at least one, so make the most out of him. Also there’s technically nothing stopping him from being the army’s General.