1/ Hunter: this quest is win condition, Hard to imagine it not work when even the processing reward already huge value (0 mana hero power), I expected this will be tier 2 deck at least
2/ Shaman: also a win condition ( or at least could create new archetype)
3/ Warlock: this probably the hardest quest so at first i dont really rated it but after watch Regis play it, i'm convinced this could be a new archetype. The reward is insane at late game
4. Mage: similar to warlock quest (hard work but big reward)
5/ Warrior: honestly, i dont know. Like we have so many pirate warrior version through hs history but most of them are aggressive while aggro definitely wont use this quest so a mid-tier place probably the safest bet.
6/ Paladin: while this infinity better the Marsh Queen (hunter queen in ungoro), it still has same issue: you can put too much 1 cost card it you deck because they will hurt you late game. Also if you just want to upgrade the dude, there are much better options.
7/ Priest: look very similar to the current cthun priest, you definitely build a slow deck for it but it either you already won (and dont need it) or you die before can use it
8/ Demon Hunter: uhm, the effect is strong but only apply for half of you deck so not worth it.
9/ Rogue: parasitic card like this need more support to be good and sadly, there aren't enough of SI: 7. The reward also doesn't look exciting
10/ Druid: the processing reward is bad and also the final reward so yeah, its just bad.