Here is a list of my leading coins and a simple reason why.
Bitcoin
Bitcoin is the single largest and most recognized cryptocurrency in existence.
Stellar Lumens
Stellar Lumens is a similar technology to Ripple; 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 etc., wouldn’t twist facts based on their needs.
Monero (XMR) — privacy enabled by default. There will always be a demand for an anonymous channel for commerce.