So far infrastructure coins were the best investments. EOS, Icon and lately my personal favourite Zilliqa (which is the best one out there nowadays IMO). However, today you can find a project which promises 1M tsp in every corner... time to move on and focus on real projects, blokchain infrastructure is getting ready soon (wait for 2nd 3rd generation blockchain to release mainnet).
The problem is that the other coins such as bitcoin cash or ZEC can be used used in side chains having similar function as the EOS.