I'm sure everyone has different needs and expectations.
Count me in the group that is looking for improved image quality. I really do appreciate the top LCD screen and the rear focus button, but I need a bit more than that to justify the purchase. My purpose is to use the 77 D as a vacation and walk around camera when I don't want to carry my 5D3. It needs to have good enough image quality that I don't feel bad that I left my 5D3 behind when I look at the images in Lightroom. Obviously that's extremely subjective! ;D
I would also like to use it as a backup to the 5D3 when doing paid photoshoots.
The complicating factor is that I currently have a T5i that has fairly good image quality by my standards, so in order to justify a new APS-C camera, I need to see some improved image quality beyond what the T5i provides. Mostly I am interested in having a bit more dynamic range, like the sensor in the 80D is supposed to provide.
So far, I haven't been able to confirm that I can expect much improvement, so I am going to wait for more reviews.