I have big hands, but I use the Canon 1Ds Mk111 & the 1D Mk11n’s without any problem and prefer the feel to the latest Nikons. But they are bigger than the 5D Mk11.
The switch was a painful move cost wise, at the time given that I have lenses from 17mm upto 500mm, a number of camera bodies and flashes. It was certainly an expense that I would rather have not had to have done. But at the time (The launch of the Nikon D2x which just didn’t cut the mustard) I was so concerned at the difference in quality that I had to make the move.
At the end of the day it all comes down to what you like and the budget to make it pay.
You are correct that Canon does have a small chip set of lenses, but these are not part of the pro lenses system. they are mostly budget priced.
Where as Nikon stated to the Press & pro commercial market that their way forward was never going to be full frame chips. They then launched their pro small chip lenses stating that they was not going to ever replace the lenses that would cover full frame 35mm. Nikon has now had to walk the dog backwards, as they say. I know a lot of Pro press photographers when upgrading swapped lenses, sold off their old ones to help fund the change over, to now be in the same position a couple of years don the road. Most of them are rather upset about this.
This is something that Canon never did. Their aim has always been to make cameras full frame.