There are very few astrophotos here taken with a K-70. It's nice to see one. The colors you got are good, so it looks like the K-70's sensor probably has decent H-alpha response. Given that its Sony sensor is quite different from the Sony sensors in the K-3, K-3II and KP (their sensors don't have on-sensor PDAF) there was no way to be sure without seeing photo evidence.
I’m very satisfied with the results I’ve had so far with the K-70. I’ve invested in an 8” Newtonian, guess that’s going to be a real test of the capabilities of the camera (and me as well)