There's nothing worth mining now because it's hard to compete with BTC at its current block reward. This may all change next year if BTC price doesn't double by the time block reward is halved.

The whole thing kinda feeds on itself, think the kindling model. Bitcoin is strong because it's strong; because a large, expensive network of miners is behind it. Turn that network to a clone coin, and bitcoin's no longer strong, the clone coin is.