Quarter Panel Patch- Stupid Question

I have always replaced the least amount of any section possible which was (maybe is) the old school idea. Replacement panels of long ago did not have very good matching detail lines and a lot of them need to be majorly reworked before they looked or fit even close. Then there was the quality of the metal. Most people found that for the best looking repair. You'd buy a parts car, most generally a cheap old, know body wants it any way, four door. Take your repair needs and scrap the rest. Now having said all this. The replacement panels I have purchased in the last several years seem to be more up to standard. Most still need some reworking but not like before. If I am able to get an entire panel at factory seams. I replace the entire panel. If it's a patch panel then I plan out the replacement to create the best repair I can. Taking in to consideration, detail lines, warp-age, access to the back of the panel, and ease of work such as grinding, paint repair and again, access to the back of the panel.