Firstly with 'tina herself. Positioning seems to be the key with her, she works like a turret dishing out angry snowballs. I try to find a place to set her up with good line of sight and within range of where the enemy needs to go.
One focused attack with a stone dropped for a mask to hit again is better than two normal attacks. The plus to damage makes her scarier on that first attack and the free attack can clean up. The third ap is usually either a pot shot or more likely throwing up ice pillars.
Ice pillars are great they mean you can protect your crew, or block off theirs. Plus throwing a low tome for the card draw is a great bonus.
I tend to run Raspi with cold nights , armour of December and seize the day. This is because Ice pillars are amazing , a push is better than a walk, and getting initiative negates (slightly) what ever stupid position I left myself in at the end of the last turn.
The rest of the crew hasn't seen too much experimentation yet but I'll go through the models I've used and try and explain why (or pretend I know why)
Firstly is the wendigo, cheap, tough, and can throw up a second lot of ice pillars. He's also a minion so counts for plenty of strats and schemes.
Arcane emissary. Firstly an amazing model apart from the fact it's too pointy. I use this fella as the muscle in my crew, his main job is to charge in and hit things then keep hitting things. Its nothing clever but setting this bull up for a massive charge is fun. 4/4/5 damage from his on the charge attack and then a decent follow up attack to finish things off he can smash the right targets. using his zero push then charging back in is definitely worth a try too.
SnowStorm. Another big beasty, I have had a huge amount of table time with the duo but I've enjoyed what I have seen so far. The beauty and the beast pair are great for getting Raspi into and out of the action with the zero place action. The ranged attack is decent with the bonus of being able to push frozen heart models about.
Ice gamin. Boosts raspi's attacks, drops the odd marker, is there. His jobs is simple but he does it well.
December acolytes. Great models. Not fast but from the shadows get them where you want them. They have a great harpoon attack which dishes out slow and the can help get around things like armour too.
The other regulars in my lists have been Cassandra and a Malifaux raptor. This while being slightly off theme (off official theme anyway my internal narrative has then carnival trading services with Raspi for passage through her mountains but that's a different topic)
This combo make the more marker heavy schemes simpler than they normally would be with the cold footed December
I think that is all for now. I keep plugging away with the cult and hopefully find my feet with theme as I get some more experience. Next up I'm going to be adding Colette to the party so I can swap between her and 'tina as the game calls for it.