Couple of things you may want to look at. First is how the licensing on your VM software works out with the change in ram allocation. Second is redundancy with the fusion I/O drive, what are you going to do if that single component fails?

"If my memory allocation is bigger than my database what are my bottlenecks? CPU and Disk Writes?"

What does the existing load look like through your entire I/O profile? I've seen enough poorly designed vendor applications that this question is likely going to be very specific to your environment. "It depends", especially throwing this on VM, reservations, over provisioning and balloon drivers now go into the mix.

It may be worth it for you to make a call to someone like Brent Ozar's team, or just spend some time looking at some of the vast amounts of free information he's published online.