Always for me it is best option to have 50% BTCÐ, 50% Alts, some coins I hold now and why:
Bitcoin
Bitcoin is the single largest and most recognized cryptocurrency in existence.
Stellar Lumens
Stellar Lumens is a similar technology to Ripple, however, instead of focusing solely on the banks they have built a system to integrate merchants, banks and the general population.
Historia
A novel idea. To keep current happenings on the blockchain. To ensure that in the future third parties politicians and etc wouldnt twist facts based on their needs.
Monero (XMR) privacy enabled by default. There will always be a demand for an anonymous channel for commerce.
Till now I still mining Moner, Monero is a good and worthy coin to buy, I also always buy since 2016, hopefully with the improvement of the market today can make Monero skyrocket again.