I'm keeping my 7. I have too many things I want to buy, and I intend to ride out my Hermes AW7. All my bands fit nicely so I'm really content. Also happy I have the cool Lucky Horse and Circuit watch faces, they go really nicely with the bands I own.In the AW cycle (excl Ultra) there's a redesign year, a minor update year, and a processor update year.
S10 is the redesign year. So you know what you'll be expecting next year. However, buying a used S10 at a good discount next year will probably be the best bang for your buck opportunity in the 3-year cycle.
But if you really like the 10, you should get it. I'm okay without it. But my battery health is at exactly 80%, how much do you think it will cost me to replace battery if my Apple Care expired?