Yeah, I noticed that as well. I haven't promoted my Cat Pirate (Steady Charlie Hawkins) yet but, as you put it, yeah unlike most side companions, he gets no new attack. I think KI did this on purpose because since the bundle was to never, and I quote, -NEVER- be re-released or even face-lifted, they didn't want to overpower the companion and multiple people wouldn't be able to get it and it would be kinda like a show-off companion no one could get. But considering the whole Ninja Pig companion thing, this may not be the case.

Maybe the actual Cat Pirate mob is just like that and they're was like point in redoing him or adding a new attack. Or the Cat Pirate never had another attack. I don't know, but I agree, he could use another attack, other than his Critical, or another promotion. One more talent would really make him useful in battle. Just leveling up his Accuracy, Dodge, Health, Amor, and Resist is great, but it's really hard to keep him alive in battle, as he is. If he's anything but third place that is. He's a great finish-offer when an enemy as taken some serious hits from Sarah Steele or Subodai or Kobe.

Cunning Finnigan Sharp
Level 17 Swashbuckler