some coins that have good prospects will have a big advantage if they are dumped like AE, DEC, CS etc.
Right, some altcoins may have value in the future but in my opinion dumping bitcoin and ether in exchange for altcoins is not a good move since those two crypto are on the top of the marketcap and whatever happen to those two, other coins will also be affected. They are some sort of a baseline for other coins in terms of price movement.