Jorah + Flayed Men is pretty great. Being able to use their panic token as Vulnerable (or in a pinch, Weakened) is strong
His tactics cards are great, too. Superior Flanking really helps Screamers and Outriders shine
I hadn't considered his synergies with Flayed Men, that's a good point and since Flayed Men are still cav they go well with the rest of the tactics cards as well.
As for Jorah's specific cards, I'm not so sure I'm quite impressed yet. Superior Flanking is really good, and Bravery in the Face of Death is quite potent if for the ability to regain wounds on the charge after doing things like Swift Retreat or Hit and Run since Targaryens really do not like being stuck in. Martial Prowess is always quite good, it's one of my favorite cards on Rodrik in my Starks lists. But in general I don't like playing my Commanders because of the cards they provide since it'll always be, to some degree, based on luck of the draw.
I'll have to try him out, though, once I get some Neutrals in to make up for his points usually being a solo/attachment. I think there's a lot to like, especially with the ability for Targaryens independent of Flayed Men to throw out Vulnerable tokens like they're candy with lots of Outrider Ko attachments.