Is Premiere Elements 2020 a memory hog for any of you?

I have a similar question having just upgraded my PC and loaded Premiere Elements 2020. System is Windows 10 Home 64-bit, 16 GB RAM, Intel Core i7-3770K CPU @ 3.50 Ghz (4 cores), C drive 250GB SSD, D drive 2TB SSD.  I have put the Adobe programs on the C drive (in the recommended place AppData Roaming etc.) which still has about 140GB free space; and store all my data, including many videos, in separate folders for each project on the D drive, which has about 740GB free space.  I am editing some pretty big projects (e.g. Nepal holiday with about 413 avi source files, unedited running time 2 and a half hours).  The media cache database is in AppData and set at 5GB - half way; and all the scratch disks are set to 'same as project'. I render the timeline frequently, but that takes at least 15-20 minutes. I have also disabled as many background services as would appear safe to do so. I still find editing is a fragile process and need to re-boot occasionally for the project to recover after hanging.  Am I doing anything wrong, is my PC not up to the job, or should I try other settings such as copying my data and all the working files temprarily to the C drive for each project? Advice would be much appreciated.

"The difference is that I am editing HEVC"

The significant advantage of HEVC is file size, not picture quality.  To get video stuffed into a smaller box without losing quality a lot of processing is required.  Decoding is the same.  It may be that your output times have slowed because of your change to HEVC, not because you've moved from version 2019 to 2020.  

"My operating system and programs are on a 500 GB SSD and I usually move my project files from my 2 TB drive too the SSD."

Before we had SSDs the video processing bottleneck seemed to be disc read and write speeds.  The buss connecting drives was fast and could support multiple discs reading and writing simultainously.  With SSDs, it seems to have shifted.  If you have the editing program, source media and output on the same SSD, along with a good dose of RAM, video processing goes on at "electronic" speeds rather than "mechanical" speeds.   

With that processor, I don't think you'll see a huge boost in performance by doubling your RAM or splitting your project files from your program files. It can't hurt -- but you've got lots of power.

Just render your timeline whenever you see a yellow orange "render" line along the top and, whenever possible, ensure that your project settings match your video specs and you'll get the best performance you can from Premiere Elements.