I got one of the Fossil Hybrid Watches. Looks like a normal watch (that was important for me) but has an eInk display in the background. I've disabled lots of notifications but it still keeps track of various data without a hassle and relays important messages to the watch face.
Battery lifetime on a charge is... I don't know, maybe I charge it once a week or every 10 days or something like that?! It's not so often that I find myself doing it conciously, I just sometimes take it of at night and leave it to charge.
I'm in a similar boat - I pretty much use the watch for HR tracking (as a proxy for stress), but otherwise keep things like the notifications disabled. This gets me about 20 days between charges
However the biggest problem is that the eInk screens seem to be a major failure point - even when working normally it seems to suffer massive burn-in making it unreadable after a few months.
My first watch had the screen die due to what I believe was trapped moisture (the weep-hole on the back is easily clogged) and just a few days ago my current watch also had the screen go bad.
It's really sad because the feature-set is almost precisely what I want, at exactly the price I'd like to pay
Similarly, I'd also suggest the Withings watches. I love mine. My battery lasts about a month but that also depends on how active its smart aspects are (like vibrating, the display, sport activities, etc).
Battery lifetime on a charge is... I don't know, maybe I charge it once a week or every 10 days or something like that?! It's not so often that I find myself doing it conciously, I just sometimes take it of at night and leave it to charge.
Was around 150 € which I found okay.