Buying new coins is really risky because new coins is on stage of developing. We can buy new coin but we need to select a kind of coin that is high potential and maybe high on demand. For me I will surely buy more sold coin which is proven and tested that can give a huge return fro me our investment.
Looking for new coins is better but here the OP is asking for those new coins which just hit the coinmarketcap, means that which just came up recently to the market. In that case I will suggest that he have to invest in those new coins which have a great project and the developers are very active for the further development of their projects, they will give you a good return.