Well I'm not going to lie, these cards look terrible so far. Vesemir change is nice, I'd much rather a more interesting deck built around Witchers than just "Muster them out". The Bronzes are awful though.
Skirmishers - I'm not sure Skellige needed another way to discard. Its either OP (it targets a card - so basically a 12 strength bronze play that thins the deck) or pretty weak (a random card gets discarded). Not really needed.
Assassin - absolutely destroys anything that already isn't already played - I.E. anything that buffs on board. So Light Longships, for example, can instantly be shut down. Other than that, it can't deal with much. It can't even deal with Axemen - they have armour, which would not be included in base strength.
Magni - just generally unnecessary. In fact, it just gives your opponent information.
Tutor - a good idea, but will probably be a bit slow. Works well with Sile, but I can't see that combo ever being worth.
PFI - nice to see it back, could be pretty good (if the tokens are 3 strength the buffing with Kaedweni Sargeant could be fun. I doubt it though, it would be a 12 strength bronze base then). Probably the best of the cards.
Hopefully these will see some changes before they come to light. Its still early days yet, but none of them seem to add anything important to the game. Dorregaray isn't great either, the options just aren't good enough.