The only way I could foresee a cryptocurrency where, by its nature, the early adopters would not have a significant amount of money in the eventual economy, is

The only way I could foresee a cryptocurrency where, by its nature, the early adopters would not have a significant amount of money in the eventual economy, is to make the rate of money generation grow with participation and / or transaction rates. The former is effectively impossible to judge, unless you use the block difficulty as a measure of popularity, and the later seems like it doesn't accurately reflect the market cap - coins like doge had much higher velocities than btc at unique times despite being a fraction the size. The other option might be a blockchain that doesn't do time based payouts but does volume based payouts. Rather than having blocks issued on fixed intervals you could have them dynamically issued and computed based on the previous blocks time to reach a calculated size threshold to hash. Unless you were psychic and could guarantee your coin would take off, investing the electricity to generate bogus volume would be a tremendous gamble in resources to try to beat the market.