Funny you should mention the A6000. That series was my first choice when I began researching. I went back to a compact idea because I didn’t want to have to choose between specific lenses for each dive ( plus price per lens and port)When choosing between the G7x-Series or the Sony RXxxx it really depends on what your preferences are.
I like the colour algorithm on the Canon and I think it is suited better for underwater - but again it depends on what you personally prefer.
First I upgraded to the Sony A6000, which honestly speaking for underwater photography is probably one of the best deals out there right now (Price & Performance).
But because I take a lot of videos I finally ended up with the Sony A6500. The A6500 got the same sensor as the A6000 and pretty much the same specs, but overtakes the A6000 when it comes to video-performance (build in Image stabiliser, 4k, super slow motion, just to name a few
Is it possible to use an A6xxx series camera with a “kit” lens and still get good results. ( using wet lenses like you would with a high end compact)
Also, once in a housing, is the size much larger than the compact? I’ve seen them in Best Buy, but never inside a housing.