Litecoin, Bitcoin, and possibly xrp.
Litecoin is much faster, cheaper to send, way undervalued, and will become scarce as institutions buy it up. It also is easier to evolve with a collaborating development team and foundation.
Bitcoin, due to being the first one and recognizable, being used as a store of value as insecurity with fiat increases, etc.
XRP because if it is adopted by banks, despite having billions of coins, could become a mainstream tool for banks, etc.