Canon has a niche with the 8-15 f4L USM, but that won't take long probably as Samyang, Yongnuo, Sigma and all other brands are producing more lenses lately.
In past I used the Sigma & Canon 15 2.8 fisheye's for nightclub shoots, this still has that something (partymood) in comparison with a standard 24-70 2.8.
Next to partyphotography I do often photography of impressive abandoned places or modern architecture.
Mostly rectangular on 16-17mm, but it would be nice when visiting some wow locations, to experiment on 8mm, 10mm,....
I know there is a Peleng 8mm and Sigma 8mm, but these are primes, so limited usuable, or have to take crops.
Are there any fisheye owners here that would be interested to use/experiment with a 8-15 fisheye on their fullframes at an affordable price from the alternative brands (or without AF, price would drop a lot).
In fact an 11-24 (non fisheye) would also be nice from cheaper brands, time that alternative brands start to produce more of these kind of ultrawide & fisheye zooms 
hey I enjoyed your youtube video on the 5d4 



