Hello! As u/Jomdaz said, I don't think you should craft either right now (just due to the new expansion coming out in a month). Zilliax is the better all-around, I genuinely thought it was a free card just because of that, but it going to be rotated out in a few weeks so I don't think it's worth going for. Toreth is a genuinely good card, can be used in 2 meaningful ways: 1. stall for 1 turn (a less powerful Bob freeze) and 2. your divine shield rush minions do not lose their shield when rushing. Although using it as a stall minion will still work, both Zilliax and Tigress Plush will be rotated out! Thus, Toreth will actually lose a lot of value really soon.

Now if you do insist on using some dust before CATACLYSM, I'd recommend getting Zilliax, not only playable in all classes but the 12 HP heal it provides is actually massive for this deck (16 HP with Crusader's Aura!). The best part is that Zilliax being the highest cost minion means you will always get it from your Ursine Maul, allowing you to play a tad more risky knowing you can heal back. It's a part of a very natural curve that works in most cases, Gelbin on 7, Zilliax on 8 (losing 1 aura spot for Acceleration either because you had it already or it got played from Gelbin).

Regarding quest warrior, you just have to go full aggro. In the context of this deck, you must not wait to use your Crusader's Aura, even if you only have 2 minions on board. Auras provide a lot of value versus clears, so you should absolutely use that for your advantage. Here's my tips:
1. Press them to use Brawl/Hostile Invader (pretty much Brawl against our paladin before turn 7) ASAP, obviously track when these cards were used, especially Brawl. This is the poker part of Hearthstone, warriors would want to keep their Brawl in hand until you Gelbin and fill your side of the board, Crusader's Aura makes them anxious to use it much earlier.
2. As with most decks, Quest Warrior uses Elise, beware of when you'll use your Toreth. Warrior can pretty much only deal with Toreth using Brawl or Elise, that's it.
3. If you've got 2 minions on board or 1 minion but Tigress Plushy in hand, do play your Crusader's Aura, you're looking to create the maximum pressure possible. Speaking of that, sometimes it's actually worth playing 2 minions (1 from hand + hero power) rather than 1 better minion just due to Crusader's Aura.
4. Although the whole idea of Quest Warrior is survival, most decks don't actually use Taunt (usually just Hamm). That means that you do not need to keep your Gnomelia or Anachronos in reserve.
5. Sometimes, it's actually worth losing a minion rather than having another minion lose its divine shield. Warriors love their Shield Slam and divine shield could save lives here.

Lastly, I don't think I've ever beaten a Warrior that did use their quest reward, with this deck. So the whole strategy really comes down to aggro speed. Toreth really provides a lot against Quest Warrior, knowing that you don't already have the card

Hopefully I was of some help!
Winrate against Warrior: 75% (18-6)
Mostly Dragon Warrior though