I believe that the only tool that can tell you in which coin / token you need to invest your money, and in which not, is your brain.
You are right, now there are more than 2000 coins and tokens and 95 percent is rubbish and fraud. To choose a promising project, you need to think very well with your head and be able to analyze.
Yes, using our brain must be the right way of finding potential altcoins. We cannot expect anyone will be suggesting good things for free of cost. I mean not all people will not be suggesting good here but there are only 50% of chances for accurate predictions from this community. So, it would be much better to go with our own skill set. Once we start studying and analyzing coins then we will gain experience then we can easily find good potential coins by our own.
Still, this community could be used as a first layer of filtering out. Like, take the suggestions from people here and then go for studying them. Do not rush for your investment with the blind suggestions.