Bitcoin is my first choice...
Ethereum is a solid coin to consider as a number two choice.
What do you think about NEO? for me I believe it's a good project, ripple is good too to mention only but few.
In many cases bitcoin is not only the top choice to be in your portfolio in some cases it is the only choice and I cannot blame people that think like that since bitcoin as an investment is so much better compared to all the no name altcoins we have in the market and that can disappear in a matter of weeks after you invest in them and you do not want to be the person holding the bag at the end or the amount of money you could lose is astronomical.