Owning the 35/2.8 in the past and owning the 35/1.4 now I can say they aren't anywhere in the same league. Outside of them both being 35mm lenses they're barely even playing the same game. So while stoping down may bring the sharpness closer the rendering will still favor the Distagon IMO. The Loxia surpasses the 35/2.8 as well. The Distagon surpasses the Loxia IMO and the opinion of many that own both.
No it's not the lens for everyone due to size but for those that can look past that you'll buy a truly remarkable lens.