What are the top 30 currencies or pairs to retail traders?

the best ones are the 28 major and minor pairs however for trading them profitably, besides having a profitable strategy in general, you should know the character of all of them to some extent.

for example, some of them move more than others within a day. some are more volatile and as a result get larger spreads. some of them such as major pairs are more liquid so they are better for example for scalping.

maybe the question should be more specific. for example, what are the best pairs for scalping, swing trading, trading on news, and etc.

anyway, I think this is a good post for knowing them better: