I would go for this. I would love to be able to sub-specialize industries, just to give them a little more variety. I am not sure the best way to do this though, as adding in a tone more products that would need to be managed would be. . . less than ideal, given our current reliance on cim job dispatch algorithms. We would need something like the building connection functionality in Enhanced District Services at the very least.
So I guess this is a conditional "Yes" vote, but based on a condition we will likely never get.