I'm still getting by with my Pebble Time Steel, and I've been watching (no pun intended) Fitbit's releases to see if they're yet up to snuff. It looks like the most recent revision of their smartwatches would work OK for me (and add HR sensor). Don't know if they'll be sufficiently reliable, since this has been a weak spot for Fitbit in years past.

If I'm able to eke out another 2-3 years, I might get an Apple Watch, which would presumably have 3-4 day battery life by then.

The versa is a good option, its the one that reminds me of the pebble the most.

Nothing has gotten to the size of my my pebble time round though

I have a Fitbit charge3 and I really like it. I have only had it for 6 months, so I can’t speak to it’s reliability.

The only thing I wish it had was an alarm that would wake me up at a specific level of sleep, like rem sleep.

I tried the charge3 and the step and stairs-climbed counters both read wildly incorrectly. It also had a tendency to track steps taken when driving. They also hadn't got the pulse-ox sensor doing anything at the time I returned it.

The OS on it is quite nice, the iOS app isn't bad either, but the inaccuracy just drove me nuts.

I moved on to a Garmin vivosmart instead. Not quite as pretty, but a lot more accurate.

Garmin watches have a week battery life and an always on display!

I second this. Garmin's wearables are excellent. My Instinct gets almost 2 weeks if battery life with approximately 30 minutes of GPS run tracking 5 days a week.

I've an amazfit bip; battery lasts about a month...

I second the Amazfit Bip. Mine lasts around 40 days per charge as a watch, heart rate, and step tracker. I leave notifications off.

Thirded. I get about a month between charges with everything turned on (notifications - the main purpose of the device for me, as well as heart rate monitoring, step and sleep tracking). Its no Pebble in terms of functionality or third party development, but I had Pebbles since the initial Kickstarter and while initially I installed every app I could find and tried to use it for anything and everything, eventually I worked out that (for me at least) it worked best as a extension of my phone display, not a replacement.

http://rebble.io/ seems relevant for you and other like-minded persons.

I've got the Suunto 9 smartwatch, it has always on display and battery usually lasts around 7 to 9 days.

Might want to stock up on used ones.