Alright, let's do this:
So, I do create really intensive After Effects compositions (usually 10 to 20 layers per composition) and make use of nearly every effect it has (such as pixel motion, motion blur, etc.) for many of my compositions. 32GB has been working well enough, but I recently had some issue where the computer is only recognizing 8GB of RAM; considering this, I've noticed the massive difference in performance of After Effects CC 2014 between 8GB and 32GB (8GB disabled multiprocessing, for example). This makes me wonder... given how intense my compositions are, would 64GB create a noticeable difference? I have the opportunity to upgrade to 64GB right now (possibly) for free by means of "wheeling and dealing." What kinds of performance gains could I expect by going from 32GB DDR4 to 64GB DDR4?
90% of your performance comes from the CPU. With more memory you can preview more frames and some things that can take advantage of extra memory will a little better. I would expect future versions of after effects to more efficiently use memory.
AE performance is CPU and ram. AE will use most of the system ram you can put in with any complex comps. I suggest 64GB is where you want to be with any major AE work.