To clarify #2 in my other comment, I feel like they can be transferrable from account to account so streamers can give them away, but not be available on Tribaldex or the in-game market.
How about a 1-card pack for 800 DEC, also transferrable between accounts but not be available on Tribaldex or the in-game market. This still gives the chance for a GFL and should be pretty easy to implement. The more smaller price options the better.
Too many options can cause decision fatigue. Few clearly differentiated options is good. Having many options with small changes mean new players are going to have to learn more and make more calculations. Keep it simple.