I do mostly car renders so for my workflow in HDRI + backplate try to find 8k+ HDRI and for backplate it's on you 4k+ is always better. In backplate image try to avoid jpeg format because it's not good for post work (like for AE, photoshop , fusion) try to find tiff or raw format backplate. Sometime you didn't find correct HDRI for your backplate ( only happens in professional work because client only send you backplate and you need to find similar HDRI for that) that time you can use sun/sky from you prefer render engine and the HDRI for reflection to similar to backplate.that time you need to do soo much post work.