HDDs good for large storage especially if your on a budget (much cheaper at 4tb+). And SATA ssds are good if you don’t have more nvme slots.

Idle? its 30% load and for laptop 70 degrees makes sense. As long as max temp under 100% load doesn’t go over 90-95ish then its okay.

And windows caches a lot of things to make it run faster so 82% mem load makes sense. 16gb is completely fine for 90% of things as i have 16gb and the only time i ever max out my memory is when video editing or playing cities skylines, which are extremely ram intensive.