If you are not satisfied with mining calculators, you will have to search for coins for mining yourself.
why would a 6gb card start to slow down when the dags not even 4gbs yet.?
As the DAG gets larger and larger it's naturally going to occupy more and more cells/chips in the memory. Depending on how nVidia coded access to the memory you can see progressive decay of hashrate as seen in the 1070s which are now down to 25-27MH/s when they were doing 30 before. The 1080/1080Ti/1070Ti do not have this issue. My 6GB 1060s have slowed down from 24MH/s to 21MH/s on ETH dagger hashimoto but run max speed on UBIQ.
To answer the OP - wait for ETC to readjust the DAG size in a few weeks.