If you want to start your origins campaign with all the cool DLC items unlocked, by order of difficulty its pretty much same as chronological order except Golems of Amgarrak. which is harder than Witch Hunt. In fact Golems of Amgarrak is so much harder than everything else it'll leave you thinking if you're still playing the same game lol.

Sulcher's Pass is a small clearing to the west of Ferelden near the Frostback Mountains just northeast of Haven. Traveling through the pass can reduce the journey to Orlais by two days compared to the less dangerous Gherlen's Pass to the north. It is where you find Felix de Grosbois who is involved in The Stone Prisoner DLC and provides you with The Golem in Honnleath quest if the DLC is

But keep in mind that playing Witch Hunt by itself won't change much, or most likely nothing at all, the thing is that Witch Hunt is basically useless, it really adds nothing to the story and reveals nothing worthy, so just ending the whole Origins stuff with Awakening is sufficient, and then exporting your Awakening saved game over to Dragon Age 2 will be more than enough.

dragon age origins when to do dlc