So far I make a maximum bet of 0.03 BTC (around $900 bankroll). I use a lot of dice which is high speed, and just run it for thousands of rolls, and then also Roulette on mini strategy, finally of course BJ to try and make up losses.
Not bad if you already have an intention to play Blackjack. I see now the logic behind this strategy. Gathering rackeback using low house edge and fast phase games and use it as some sort of insurance when you are already playing your real game which is Blackjack. Surely you might take some losses at first but you can recover it slowly by just playing the basic blackjack strategy.
It's actually not so much if you think about it right?
Not so much but still good to have a calculated gambling for a profit. Your method is very efficient to maximize the use of 70% rakeback.