Well, why not to see price changes over the last 6 months to decide which coins to pick? Bitcoin went from $1300 to $6000, ethereum from $60 to $300, xrp from 3 cents to 20 cents, ltc from $15 to $60, dash from $80 to $300 and Neo from less than a dollar to $30. I guess, if you just keep your investments in top-15 coins on coinmarketcap, you'll get good profit. So it isn't really important to take a look at what these coins offer and whether their dev team are good. Best of luck!