My current setup as per tweakers page and Harms advice:
Windows 10 Pro
Asus P9X79 E-WS (2011 socket)
Core i7-4930K 3.4GHz CPU (Not OC'd I am struggling to do this even with the software)
Samsung 840PRO - 240GB SSD for OS & Software
2x 3tb 7200rpm Seagate drives in RAID 0 for footage and project files (onboard RAID)
Samsung 830 256gb for Cache
OCZ Vector 128gb for Exports
32GB of corsair vengeance ram
GeForce GTX 780 Ti
Programs are all setup to use cache disks which are cleaned regularly, all drives have more than half the amount of space free. Years later, PCI-e SSDs are still crazy expensive.
What else can I do to speed up After Effects animation renders, & Premiere Pro video edits, either by tweaking the current setup or by spending money on new hardware?
you should check if the cpu usage is near max while exporting/rendering in premiere and AE. if its not you will need to identify bottlenecks, software or hardware, to remove or reduce them and get the cpu usage up. the latest versions of AE may not max cpu usage as its not properly coded for multi-core cpu's. you would have to use an older version of AE with multi-frame rendering to get around that.
if the cpu is near max % usage, then you would have to look at increasing cpu performance. that could come from overclocking, or upgrading the cpu to a higher core count xeon v2 that still has high clock speeds around 3ghz, or a new x99 8 core or higher build. if you are working with HD projects with premiere, the higher core count cpu's may make things worse, they help more with 4k projects.