Eth definatly got the bigger momentum at the moment.
But difficulty is rising fast and lot of miners will direct their hashing power at etc, hopefully leading to opertunities for etc.
Also eth is going to pos, again leading to a lot of hashing power to etc, hopefully leading to increased etc support and development.
Etc will have to reinvent it's place in the ecosystem i think, but it will be a lot easier with support of the miners coming from eth.
As for the coin itself, there is no reason why it cant get as big as eth, it all boils down to the dev team to make good improvments and marketing.

For me as a miner it will possibly give greater returns to go for etc just bacause i can accumulate greater numbers of them. I will make a lot more money on etc rising 10$ then eth rising 200$.
Hopefully i wont regret not trading my etc for eth in the future hehehe