If I have one BTC to split into Altcoins I would split into those coins which are solid technology wise,community wise LIKE ETH.Some coins which are also very good and undervalued like NEO,ADA,EOS,MIOTA.These coins are gradually growing and will increase tremendously in coming few years.I will split as
1. 70% into ETH
2. 30% into NEO,ADA EOS,MIOTA