Please, mrsfotografie, tell me why are you not happy with the Rokinon 12 mm f/2.0?
It is supposed to be of very high optical quality and reasonably priced. In fact, I though I might actually get one.
As you said, there is so much more tempting stuff from Canon for the EF that you'd really have to be a Sony fanatic to buy a Zeiss Touit or whatever for 1000 dollars when you can get a 16-35 f/4 at that price and it is quand meme something else, totally. Value is something where Sony is seriously lagging behind.
My experience with the Rokinon 12mm f/2 on the a6000 is very good. It has some CA but it's about what I expect from such a wide lens. Color is great.
It's very light weight and the focus ring is stiff but I have lots of practice with MF so it's not a problem for me.
Focus peaking is ok but I prefer to use focus magnification and I can nail the focus every time, easily.
The resolution is very good and works nicely with the high resolution sensor to produce great detail.
I gave my Canon gear away because I was so impressed with the results from the Sony system.
I'll upload some samples:
Note that the images were resized during upload, so some quality may be lost.
I always shoot in the "Neutral" profile, no HDR or heavy processing/manipulation.
This first one has no CA correction, -7 highlights, +11 shadows, +9 clarity, +15 saturation in Lightroom
(ISO 100; 1/50sec; f/5.6)
(ISO 400; 1/30sec; f/4ish)
(ISO 3200; 30sec; f/4ish)