I turned off in game help advice and Janusk no longer shows up... your mileage may vary.

Janusk scares me. I let him die in my first battle, and he still sends me tips from the grave!!! Be gone demon!!!

He's not free.  It's 10 gold to hire him (may vary with Charisma).

I have actually had a couple of game where for some reason he didn't show up or I met a wandering hero before I met him.

He's always free in my games, I don't know why anyone would pass up a free +1 gold merchant ability .. I think that's what he has. I typically buy him travelling boots right off so he can move three squares a turn and you can cover twice as much search right from the getgo.

Janusk has a semi-random appearance. I've had him be the bearded red guy, a Tarth-looking Bard, and an Arabic kind of guy.

I'd prefer an adivsor from our own race though. Janusk isn't memorable in the least...yet he gets a front row seat to the whole game. You could replace Janusk with a randomly generated model drawn from the player's faction, give them a random name, and I would probably enjoy them more.

Janusk makes partial sense for the campaign. But they just plucked him from the camp and dropped him into sandbox. They could put more effort into it.

I just give Janusk to my enemies via a trade and he can terrorize them (Wait I wonder if that carries some type of diplomatic penalty towards the side I "gave" Janusk too)

Actually, I think he gives random abilities: sometimes +1 gold, sometimes +1 tech research etc. Those are the two I really like, I take meditative and when Janussk gives +1 tech research you can start your research without any buildings or improvements.

I don't think I've ever gotten Janusk with anything but Master Merchant, over like 50 game starts. But I'll admit I wasn't always paying attention because many of those starts were throw aways.