If not already, I'll add a little note about selling cards giving you exp in the tutorial section.
Gold packs aren't available yet in this version but will be eventually.
Harley's story will be complete in Version 0.13 so if you're sticking to free, public version, that'll be out mid-June.
Don't worry about throwing away your save file. As long as you keep it and update the game, we provide an 'update old save file' system that lets you use your old save file and update some things to minimize bugs for the new version.
Glad you found a deck-strat that works for ya!