Is it a safe bet to invest in the top 20-25 coins on coinmarketcap.com? Im looking to invest about $20,000 into some cryptos.
Nothing is a safe bet. I'd suggest you do some research on projects and platforms, and then invest. $20,000 is a fairly significant amount that warrants a thorough research. Spreading it out blindly isn't usually the solution.
If it is a lot of money for you. I think it is a little risky. I advise you to invest half of your money in btc or eth. Not very big payback, But the risk is low.