2012 Prius V runs awesome but

Last month purchased Prius V 2012 from a used car dealer.My husband changed oil and it was black and changed transmission fluid and it was very very dark also so QUESTION it runs great but was not likely well cared for, it has 185000 miles, I get 56 mpg when I am focused on it(all the time!) I was wondering does anyone think we should change sparkplugs and ignition coils? There is no codes and no lights and no apparent trouble. It does have a recent Jan 2022 hybrid battery replaced. Very pleased with my old car. Thankyou.