I've been around the block with fitness trackers on Android before, and just recently. I have owned the Gear S3 Frontier, the Ticwatch Pro and the Fitbit Charge 2. Not a single one of them are as accurate, or robust as the Apple Watch. None offer quite the level of cohesiveness that it and its bigger sibling (iPhone) do either.
The Gear S3 was the best of the bunch when it comes to synchronization, and it works great with my Note9 in particular, but its fitness tracking is not good. It consistently drops my HR while running and is too heavy to wear comfortably for exercise because of the heavy materials. Also, in my opinion, circular watch faces do not translate to good use with the OS. Samsung has adapted Tizen to the circular face in some areas, but certain things, like notifications, are styled in a rectangular fashion, with information sometimes getting chopped off. Hard to explain that without seeing it. It feels a tad sloppy is all. The Gear S3 is the best of the bunch I tried overall though.
The Ticwatch is just plain inaccurate. Steps counters are way too high, which I rely on every day. That's a notorious problem with any Ticwatch model from my research. The HR sensor keeps my HR consistently but doesn't deliver accurate readings. The watch design overall is nice, but the construction kind of feels cheap in my opinion. WearOS is a bit of a mess as well. It's not nearly as robust as Apple or Samsung's OS, and really needs to be fleshed out. That's probably why there is no Pixel watch coming if I had to guess.
Fitbit is solid overall, but just not as engaging. I've really got no qualms with it at its price-point and objective. Fitness is my main concern, and it's great at tracking fitness, it's great at tracking sleep as an added bonus and the Charge is a decent enough looking device. But it's not good at functioning as a smartwatch, and they don't position it as such. It's definitely tougher to interact with vs the Apple Watch or Gear S3 and at the end of the day is simply a one-trick pony. Its a steal at the price point, but I'm willing to pay more to get more. They have the Ionic, but it looks cheap, feels cheap and is priced too high for what it actually delivers in my opinion. Fitbit is also a fitness-focused device but not an overall health focused device. That's where the Apple Watch excels, by letting me use the Health app to log my activity, heart rate data, heart rate notifications, soon-to-be EKG, etc. I feel like Fitbit is focused more on your health today, where Apple Watch is focused on your health tomorrow, if that makes sense.
Apple Watch, and the 44mm specifically, is also the right size for my wrist. It's much lighter than the Gear S3, while not feeling cheaper like the Ticwatch or Fitbit. I already have all my old bands which still work, and it's just such an incredibly cohesive experience with the phone. They've given added function to the watch faces (they may never make another watch face more beautiful than Infograph), which was a complaint I had before. It's noticeably faster than even my Series 3 was. All-in-all it just delivers the best combination of watch and fitness tracker, bar none. I had a feeling if anything pulled me back it would be the Apple Watch. I had all but sworn off the iPhone just a week ago too.
Sounds like your are prioritizing watch over phone. I dont wear watch, so I dont attach importance to it. Think from your description, you are just using your watch for fitness tracking which every watch in the market can do well (from the very cheap to very expensive like iWatch)
Personally, I think the iWatch is just too flashy. People know immediately your are wearing an apple watch. Of course, some do like the attention. If I were to get a watch it has to be how a watch suppose to look from very beginning i.e. round. Personally the square face is just bit too tacky for my taste.