A buddy of mine just made a pretty sweet video covering the basics of macro photography.
He's planning to create a follow-up video covering more advanced macro topics and is looking for suggestions?
Link will follow. Moderator
I'd skip the 7Dii - it's old and the image quality doesn't hold up to the sensor of the 80D. Give the 5DmkIV some serious consideration - I've been using it alongside a pair of 1DxII's and the 5DmkIV holds its own against the big boys.
I've loved th 16-35mm focal length for close wide perspectives. The difference between 14mm and 16mm is small and the versatility of having the 16-35mm is great.