Hearthpwn

Here's a screenshot of my current deck.I have 800 dust from scrap and dusted cards and I want to craft 2 epics for it now.

I was thinking of 2 Smolderthorn Lancer's, but I'm down for suggestions or even advice to improve it?

I would take out the upgrades and put in a supercollider or two. That card is super good. What about a single supercollider and two smolder thorn lancers Instead of the upgrades and a firetree? 

Upgrade! should go.  The lancers probably help.

The changes I would definitely make:

-2x Execute, +2x Smolderthorn Lancer (better tempo, plus you should be able to meet the condition every time)

-2x Upgrade!, +2x Town Crier (upgrade is very low value and isn't good enough in this deck, town crier will make your early game better and add some card draw to the deck)

Other than that, I'd consider adding Supercollider and/or Zilliax. You can take Wyrmguard and/or Brawl for that

Edit 1: now that odd paladin has taken a hit, you could consider dropping the Warpaths. You can try Twilight Drakes as well, although I'm not sure how much health they will have on average.

Edit 2: you should try to add The Lich King as well, it's just good.

Concerning epics, some of the good ones will be rotating out. Smolderthorn Lancer is a great card, but it does lose some value if you aren't running an Odd deck and thus have access to Execute. I'd also consider a second Brawl. However, with your current deck, I think that saving dust for a legendary would be more benefitial. Dr. Boom, Mad Genius, Zilliax or Ysera would be great additions. Looking at your deck, Grommash Hellscream or Alexstrasza could work as well for some burst.

EDIT: Some have mentioned Supercollider. It's a great card but the DK already does something similar. Still, with the DK going away, I'd keep at least one copy of that weapon around.