I think it is in every way possible. First, it would help and make coin exchanges safe and easy for everyone, second experimental coin with improved coding will get more exposure. I remember the idea of introducing sidechains was proposed just not long ago as a solution but I just wonder where's the progress right now.
the interesting thing is that no side or cross chains are necessary, it really would be not different than running a litecoin, bitcoin and other wallet running at the same time in the same computer, it's just that this exchange-wallet-applet could direct every transaction to the specified coin, and updates the trade information for everyone to see.