Thank you Mark Twain...
When I start doing my research, a local dealer told me that I have to pay 1K just for the cabling. Apparently it is not. There is such an inexpensive flash cable connecting the hotshoe.
The A7 does not focus as fast as my other full frame DSLRs like D800/5D3. I have all those essential macro/wide lenses for the Nikon/Canon but as for A7, I have to wait for the newer wide/macro lenses. One way to get around is to use LAEA2/LAEA4 adapter to use old Sony/Minolta lenses. However, Nauticam housing does have space to accommodate the adapter.
I also have an A77 which I believe has image quality exactly same as your A65. Well if I shoot only in RAW, with two flash gun firing at ISO 50, I believe both have great quality.
1K just for cabling? That sounds way to much. Unfortunately I'm not well informed about flash possibilities on Nauticam housings as Ikelite delivers a all-round carefree package, but as far as I am concerned a dual sync cable in Nikonos' 5 pin style should not cost more than 200 € (with which you can use two Inon Z 240 I think which makes an ultra compact package).
Autofocus improved much with on-sensor phase detection but is still behind DSLR what I've heard so far. But with E-mount lenses I'm convinced that autofocus speed is more than sufficient for underwater and land usage)!
For Fisheye you could use the Nikonos wet fisheye lens, Nauticam has an adapter for it if I remember correctly. Macro is still an issue, I hope, Sony will release a decent macro lens within this year. Alternatively you can use the 28-70 kit lens with Nauticam's wet diopter in the meantime (sample images: http://nauticam.smug...161&k=CWXW5B3).
Maybe some lenses will fit into ports with the LA-EA2 adapter so you can use a macro lens (e.g. sony 100mm A-mount) but you need the exact dimensions to test this out.
A77 and A65 have the same sensor, nevertheless the A65 won't let you choose 50 ISO IQ is great in my opinion (with ISO 1.600 maximum).