If you want to make profit you do not need to be greedy. 20-50 percent for each coin is an amazing profit on a falling market. Do not make this mistake to await 1000 percent profit for each single coin or you will be left with nothing.
Yes, it would be interesting to see From you a list of these coins that give 20-50%.Even if you can theoretically predict the growth of any coin there is no guarantee that tomorrow its price will not fall even lower than the previous one.