I thınk you can't avoid scam ICO's if it is in your faith 
because they can look legit and after six months past of their ico they can say we are done we can't deliver this product because of this because of that bla bla.. You can protect this situation with blockchain or nothing else. If you are not a risky person you need to go on with BTC LTC and Eth or really good proven altcoins.
yes, things like this are exactly what I experienced, after 2 months I worked for them but at the end as you said, "they can say that we are finished, we cannot send this product because this is because blah blah", my heart is very disappointed to hear this, because my work is not appreciated and they underestimate it. because they can look legit and after six months past of their ico they can say we are done we can't deliver this product because of this because of that bla bla.. You can protect this situation with blockchain or nothing else. If you are not a risky person you need to go on with BTC LTC and Eth or really good proven altcoins.