I have the 8 Plus and Note 8 and have almost the same apps (some are called different names but do the same thing) on both phones. My usage does not change that much. I don't play games and take a ton of pictures.
I switch between both phones randomly...when ever the desire suits me
I work from home every other week so that week i am on WiFi all day. During this week the N8 can keep up with the 8 plus. But on weeks I go to the office and am on cell service with TMO.....the 8 Plus gets about 20% better battery life. The standby times are night and day between them. The 8 plus is just better at standby than the N8.
Those are just my experiences using and owning both phones.