I agree with you at some point, it is really hard to predict which cryptocurrency will have a good future or which will fall or just stand still like those you're holding.
Nowadays where there are so many new altcoin its even harder to see which coin is potential to have a good price in the future.
Me myself prefer to hold any altcoin which are cheap enough for a long term investment, so even if the worst scenario happen i won't feel a huge loss.