I can't say I've ever played any wargame where you can still win if you've been cleaned off the table & am pretty certain that's not the case here.
On Jack Daw, why not. Doubling up on arcane resovoir is has two benefits here. 1) More cards in hand for Raspy to cheat with. 2) More cards to keep Jack alive. The 2ns point here is extremely valuable as Jack flies foward top speed & then uses doomed to stop cheating within his range. Get him close to the enemy & have the silent one move up & cast northwind. Rasp moves into arc range & flings the curse @ Jack, his low defence is brilliant here & as you're far away you can still cheat up to fling out the blasts. Then discard to keep Jack Alive, rinse & repeat. Alternatively if you can't get Jack that close get them in range for doomed so they can't cheat then cast at them while you can.
On the Golem speed doesn't matter as the aim is to nuke the middle of the board. But he's also there as as he looks cool, can dish out bite of winter & packs quite a wallop.
I'm not really concerned about ranged enemies as I've got quite good at screening Raspy with terrain, ice pillars & other models (one being the Golem).