How does one know which altcoins come out recently and thus are trading pretty good? You can check coinmarketcap to see which coin has increased in price or decreased in price the most in last 24 hours or 7 days or month etc. But besides that, are there sites that show what coins will be released soon to the public? Thus by that i mean being able to buy from exchange like binance etc.
Here are so many sites that runs that services such as coingeecko, Ico-checker and many more, and I think the best of them for now is still ICObench, this is still the one I prefer more amongst them all because they give full details concerning the project and can even link you directly to where you can participate in it either through their site or their direct link to bitcointalk thread.
They all do rate the projects for you to know which one they consider the best amongst all the projects they have listed for any investor or bounty hunters to take note of. For coins that has been released, I do not think there is any site that follows up on that other than their telegram page, or better still listed on coin market cap after they have been registered.