The supply is certainly an indicator, but doesn't tell the whole story. If a coin's supply is huge, chances are, one coin's price will not be that much. However, instead of the supply I'd pay more attention to market cap, trade volume and overall news surrounding the coins (new partnerships, shifts in public perception, etc.).
Yeah don't focus on marketcap because sometimes coins are in the top 100 with small volumes of 10-100k and those are most clearly pump and dumps. What you should pay attention to most in my opinion is the other noise of volume and news like this person pointed out. Marketcap gives an indication sometimes but only if the volume is a fair representation of that cap which isn't always the case.
