yes no body can predict the future of bitcoin but should we really need to predict anything now. i mean a student do not eep gussing or predicting what is gonna happen next lets make it happen i know the future is a impossible stuff but lets just try to make whatever we want to bend the future the way you want becoze its yours.maybe someday i will have 10btc
How much bitcoin you need will depend on a lot of factors, like the price of bitcoin, the economic situation of the world and your lifestyle, personally I think the minimum I could need is 150BTC but 300BTC will be even better.