Despite what you think of Apple, their ecosystem is fantastic and that holds true especially for the Apple watch. I am coming from a Series 7, which is not a HUGE upgrade to the Series 9, but I definitely notice the improvements in my daily use. The Series 9 feels snappier, Watch OS feels better, battery lasts a bit longer, and just my overall experience I thought wouldn’t change much from the series 7 but it definitely is noticeable when you start actively using it more and more. the upgraded processor in the Series 9 is fantastic cause it makes Siri so much quicker in my experience to use.
I have not had a bad experience with apple watch, my battery can get through a full day and a half, almost 2 full days before needing to charge it. Charging is quick as well so even if I last a day with it, i throw it on at night and I am ready to go in the morning.