This is some very interesting analysis. I bought 300 packs during presale because I wanted to support the company with some purchases, even though I know it will be more cost effective to buy the single packs and individual promo cards. $5/rare and $34/legend are some very interesting numbers. However, people are definitely factoring the retail price of the titles as well when pricing the packs on Hive Engine, so your estimates may be a bit high as more of the pack discount relies on titles not just the cards.