Good analysis, Zcash part was new and very interesting for me!
When talking about Steem growth I think the marketap would be much better metric, because of ones crazy inflation for first 6 months. Buying steem for $1 was fantasticly good price, because supply was small. Today marketcap of steem is a lot higher than last peek, then price was at $4. Basically any moment before today was a good time to invest in steem.