Right now I’m using a Nikon D750. I’m not heavily invested into the system (24-120mm f/4, 50mm f1.8 and a Tamron 70-300 f/4-5.6) and I really only shoot stills. I want to go mirrorless but not Nikon.  I also live hours away from any kind of city that has a camera store. 
I’m torn between the A6600 and the A7III.  Would I be happy with the A6600 with the 16-55 f/2.8 or the A7III with the Sony/Zeiss 24-70 f/4?  I know happiness is subjective yada yada. But any insight would be great. Thanks!

Welcome to our forum. It‘s hard to answer your question without further information (motives, light conditions etc.)

Thanks!  Let’s say general photography. I like to dabble in a bit of everything. Trying to find out what I really like to do. I don’t do a lot of low light stuff but when I do, it’s a lot of off camera flash stuff. 

Have you considered the A7C? It has the compactness of the A6600 and the fullframe sensor of the A7III.

Your question actually has a lot to it so I feel Olafs point. If the two options you mention is all that's relevant to you, the A6600 + 16-55 f/2.8 will likely give you better results in terms of image quality. Coming from a DSLR however you may either be looking for something more compact (A6600 or A7C) or you may find these compact options too uncomfortable and prefer something more DSLR-like in the hand (A7III). Something else to consider is future upgrade path: APS-C has a fairly limited and slowly expanding lens selection but the selection is pretty decent and complete nonetheless. The lens selection for fullframe is a lot bigger and growing by the day.

I personally went for compactness a while back and bought an APS-C camera. The A7C got me tempted to switch to fullframe, were it not for the tiny viewfinder and lack of controls on that camera: the A6600 has a bigger viewfinder and 4 more custom buttons than the A7C (but lacks an extra control wheel). Curious what the A7CII will look like, whenever it comes.

Edited November 1, 20214 yr by Pieter

You mentioned that you don't do a lot of low-light stuff, so I think you might like the A7Riv.   I shoot Nikon and Sony mirrorless and often run into lots of unwanted noise with high-ISO, low light on the Sony.   I find myself going back to the Nikon D850 for low-light moving subjects, just because that camera does a great job of auto focusing in dim light.    I first went to Sony for small, light-weight, etc., but soon realized that when you attach a quality f2.8 zoom to the camera, your back to a heavy, bulky camera.    Have fun.    When people tell you, "it's not about the gear"  just remember that the "gear" does make some of us REALLY HAPPY. 

Consider a7iii + Sigma28-70 <---lightest f2.8 med zoom lens