IPhone 6s plus or 7 plus. I know the prices and what they do. But what I wanted to know is

Did the 7 fix the home button problem?
That s my main worry.

I use my phone to text, check facebook, candy crush, look up info, and take the odd picture… Will I notice the difference between the two phones to be willing to pay more for the 7?

Hoping for opinions for 6s plus and 7 plus from past of present owners.

Yes

The 7 does away with the "moving" home button completely.

Home is now a force sensor with no moving parts, so nothing to wear out.

The other differences are that it's sealed and waterproof, or splashproof at least - and no 3.5mm headphone socket.
They come with an adapter that plugs in the lightning port and has a headphone socket so you can still use wired headphones if you want, but of course it works with Bluetooth ones and you get a set of Apple's own wireless ones with it.

Through all the iphones I've had, from a 4 onwards, I've never had a functional problem of any type. I've always kept them in otterbox cases and all the home buttons are perfect.

I suspect home button failures are due to excess force or dirt etc. Getting in around the edge of the buttons, which does not happen in a dustproof case.

For some of the early models at least, Apple at one time suggested dripping a few drops of isopropyl alcohol into the button as a possible cure for bad operation. That implies dirt or contamination of some sort, which the alcohol could dissolve or wash away.

I have no idea if that applies to later ones with fingerprint sensors - and definitely do not use anything other than pure, electronics-grade IPA.