Hi
As you say, the specs of your PC are not at the high end. You don’t tell us what kind of hard disks it contains. The PC becomes a bit
faster when you have an SSD drive installed. Usually about 6-10% faster then a (real) hard disk.
Besides the usage of a faster disk, there are roughly four ways of adjusting your process an make it as quick as possible
Output format: Look at your production files. You say MP4 not ultra-high quality. Well. The lower you can afford to set the specs of these the faster the production will go. I suggest that do some experiments with that to see what balance between quality and speed you like best. (You did not tell what kind of audience you have and/or what kind of platform or media you need to serve. Some hints may help us helping you
Input format: Once you know what the production format should be, you can adjust your input files to be the same. You can do that by pre-processing them, reformat them with a tool like Handbrake. Mind you when you start with a lower quality input file and do (a lot of) editing, the quality may become lower. Also here you should experiment what input output combination suits best.
Multiply editing phases: when you have a lot of editing you may want to start with making cuts (if applicable) you make the clips as long as you need them in the final result. It all depends a bit on the amount of cutting and editing required. Once you have cut the length down to required you can produce, and you can adjust the quality to requirement here, instead of scaling it down with a Handbrake like tool. If you need mor editing, color grading and/or adjustments, transitions etc. it IS possible that the combination of multiple goes (creating the input for the next edit phase) will be faster than doing it all in one go. Mind you, multiple input-output actions will make your quality lower each time.
Program settings: You write that you already have optimized PC for your PC specs. Good. Use shadow files where possible (and if possible, because input that is already of lower quality may not have to be down-sampled), and set the preview screen quality low. I don’t think that switching on or off the hardware acceleration will help much, be again you can do some experimentation here too.
It may be that PD 365 is an overkill for your PC and your production. Depending on your requirements you may also try using the Video Editor in Windows Photo’s (available in W11, maybe also in W10). Or look for a lower version of PD. But then again if you already have 365….
Have fun.