"I understand $10 is meant to be the paywall for getting access to the reward pool, but how about maybe giving back to these players like $2 or $3 so they can actually buy some cards and get a taste for the game?
This could easily get implemented by setting up a fixed 25 DEC bonus for the first, say, 100 matches of every new account that has paid $10 to get started (so it doesn't include promo codes)."

Why not add one or two booster packs and to open this 5 or 10 mystery potions, so with luck the new player can found even a legendary and/or goldfoil card in his "starter package".