Hi John
Well, as an EU citizen you have the right to live and work in any one of 28 (now 27) nations and still retain all of the same rights as you would in your home country. To me -- as someone who has lived and worked in 5 EU nations -- that's a *massive* benefit.
I may be doing you a disservice, but I suspect you actually meant "what are the benefits to me personally?"
You know, I can remember a time (1973) before the UK joined the European Economic Community, when freedom of movement across most of Europe was a given and all that you needed was your passport. Of course we didn’t have the rights you mention but most people didn’t need them... and still don’t. We certainly didn’t need a visa and the idea put out by some that we might need a visa after Brexit is blatant scaremongering. Unlike you I haven’t worked in Europe but I did study and work abroad for some seventeen years and all I ever needed was a student or work visa. I had the same health, travel, ownership benefits abroad as here in the UK and could have voted if I had wanted to.
We don’t have to become a citizen of a political/trading block like the EU to enjoy the rights of the EU country we choose to live in (and the majority of us live in just one country). That is demonstrably so when we see the many people living and working in the UK of non-European origin. :-)