I can still afford to old the first 10 coins on CMC for or than a year and Bitcoin for as long as possible. Although, there are times that you just have to disposed those coins and buy back when their prices are low. So, oi personally do not just hold without putting it to use, either to yield more or to avoid huge losses.
It is better to diversify your portfolio when it comes to investments. As the saying goes : don't put all your eggs in one basket. However, you need to evaluate each and every coin that you want to invest with. Not all coins that are in top 10 have strong foundation. So better look for its possible long term application in the market.