I have all 3 adventures, and have completed them all the way through. After wanting a bunch of cards to create some decks, a lot of which were legendaries, I ended up disenchanting cards I thought I would just "get back" later, with dust or pack opening. I really should have thought longer about how much dust that would take. I now have 5 legendaries left in my entire collection, 2 of which I use in my main deck currently. They are:

-Sir Finley Mrrgglton

-Old Murk-Eye

-Justicar Trueheart

-Reno Jackson

-Dr. Boom

I currently have a Murloc OTK deck that I use as my main deck, which includes Old Murk-Eye and Dr. Boom. When WotOG hits, I wanted to make a Rogue deck with Brann Bronzebeard and Yogg-Saron, but the majority of the cards I disenchanted were from the Rogue class because I never really played Rogue too much (level 11- yeah basically never). I have just over 50 dust and just over 300 coins.

The main reason I write this thread is to ask, what is the best way to try and get my good cards back? Buy packs and just use my main deck until I have enough core components to make another? Or is there some other way I could get myself back up to my original status?