invest it on the worthy ico, u can gain more eth by doing that. but be prepared to research the hell out of the ico you are joining, to avoid scam ico that will run your eth.
I agree, holding your Ethereum is a good option but if you're going to invest it into good coins then it's better because some coins are now spiking up and most top Altcoins are in the good position and earned a lot of investments from young investors.