Portfolios diversification is a good step in the right direction when you do it the right way.
When it comes to eth, xrp, neo, only you can decide if holding is favorable because only you knows when you invested amongst other important details
Yes, the decision in general is really in each of us in terms of choosing tokens for holding, and of course everyone will choose the best so they can benefit in the future, if asked to me personally, all three tokens are equally good for holding, although I often have just two tokens in between, because I rarely buy Neo tokens even though Neo is also a good token.