Other than ripple, you can choose anyone from the listed coins although choosing bitcoin will reduce the chance of gaining more percentage. I would be invested into Litecoin and Ethereum mostly.
Why do you think think choosing bitcoin will reduce thr chance of earning more ? When bitcoin is the one that controls all cryptos . What ever happen to bitcoin will have a chain reaction to the rest of the coins . Investing on ripple , eth , and ltc is not bad but we should first prioritze bitcoin . You can allocate 50% for bitcoin and the rest goes to alts or you can aim for 70/30 for a better profit .
Comparing to bitcoin the price of ethereum, Litecoin, ripple and doge is affordable. From the above mentioned list I prefer to make investments over ethereum and Litecoin which will surely show big growth. In short when bitcoin touch $20k surely ethereum will touch $1000, and with Litecoin surely can get a $500.
But i think you can earn more if will invest more on bitcoin because bitcoin do already have a high base price and how much more if bitcoin price pumps ? While other coins only have a small base value and they wont also pump too much and they only pump rarely