I think, you need to choose no more than 4 coins for investments. the sum isn't really big. if you buy many coins even if them much more, you don't receive good money. And therefore you can increase the sum gradually and buy new coins for new money.
Yeah and I think new coins or low marketcap coins with high potentials are the best choice. If we can buy the cheap altcoins which can grows more in the market place means we will get the more money how the investors are making money in bitcoin and ethereum. Early investors in bitcoin are the really best people in digital currencies they made billions of dollars with the holdings.