I always go for the safe options like Waves, Stratis, and other top 50 coins in the market. I think they're still cheap and still got the capability to grow in the future and really good for long-term holding. I also want to consider buying coins that are under $1.
if you always buy coins that are safe then that is a very safe method for trading but if you buy waves I think you will be too long to be able to benefit because the waves' price movements are very slow. better you buy coins that have very fast price movements such as ethereum or others that have high trading volumes.