I have used smart watch since about a couple of years now. The first one was Fossil gen 3, I liked the experience, but had so many issues like lack of applications and pretty crappy battery life. Then I switched to Samsung Galaxy Watch 5, it was such an improvement, specifically after a software update in the first half of the last year. The watch was way more responsive, Google Assistant worked as expected, automatic activity detection along with an improved battery life (about 1.5 days easy). Then I switched my phone to a Pixel 7 for a clean Android experience (unfortunately, the bugs in Pixel made it more annoying to use than my previous Samsung Galaxy S21 5G, but maybe things are improving slightly now). For better pairing with the phone, I switched to a Pixel Watch 2.

The experience on Pixel Watch 2 is actually a definite step down compared to Samsung Galaxy Watch 5 a few months ago (which can now be bought used for the half the price of Pixel Watch 2 on Swappa). I will try to detail some of the characteristics I would like to have in a smartwatch-phone ecosystem. Along with those points, I will also try to add a comparison between the two watches (Pixel Watch 2 (PW2) and Samsung Galaxy Watch 5 (GW5), not the 6 as I have not used it).

AN IDEAL SMARTWATCH:

1. Seamless connection between the watch and the phone. I would like the watch to be an extension of the phone, but not another separate device I am using. It does not make sense, for me to set things up separately in the phone and in the watch, a good example is the Bluetooth and WiFi settings. Why would I want to connect my Bluetooth headset to my watch separately to my watch, when it is already connected to my phone? A simple button to switch the connection to the watch is better, or something ideal would be for the buds to be connected to the phone by default, and when the phone is not around they would automatically connect to my watch.
2. The Google Assistant should be a holistic experience (this I think is partially implemented in GW5). When I have my phone in my pocket, and activate assistant on my watch, it should be the watch which should respond (and through the speaker on the watch). But, when my bluetooth headset is connected, I want the assistant to talk to me in my headset (GW5 does this, if I remember). Currently when I activate assistant on my watch, it doesn't matter if I am wearing my headset it tries to answer on its speaker. This is so annoying, as I would now need to remove my headset just to listen to it.
3. When I am wearing my Bluetooth headset, when I activate assistant either through my watch or my phone, assistant should take audio input from my headset. That is obviously the best and the clear audio signal that the assistant can receive. It doesn't make sense for it to do anything else. I do not know why this is not implemented, and it involves some technical and/or security concerns.

These are optional, which I think would make the experience a lot better:

1. When I am activating assistant through my headset, and my phone is in my pocket, I would like the assistant to respond to me on my headset, and show stuff on my watch. This is specifically useful, when I am standing in a bus for instance. But otherwise, show stuff on my phone.
2. Need to add more features

This is like a list I would like to make, and I will add new points whenever I will think about one. Feel free to respond, and I will also add your ideas to the above check list. Hopefully, this serves as a review to the manufacturers (not just Google), to make it a better experience for all of us.