CoinMarketCap is great, but there are more things you should take into account when researching too as I'm sure you're aware.

There are too many to list here, but I'll be writing up a post in the near future on how I do my due diligence and assessments for trading or long-term holding.

I personally find a combination of technical analysis, good understanding of the project & technology, up to date news and blog information and a good sense or recollection of historical market similarities tends to do well in these situations.

The markets are moving so fast right now that I'm sure a lot of people are going to end up holding a lot of bags of nonsense or overvalued crypto when we reach the next cool down.