I feel like windows would seriously hamper the experience, it’s terrible on small screens and when you don’t have a normal mouse and keyboard to use. It also has a ton of overhead that’s going to eat into the more limited CPU and GPU.
I’m also pretty sure you can just dual boot windows on the steam deck if you want to have windows available.
I like the garmin venu 2 that I bought used, it’s been very reliable. I pretty much forget about it since it just works with minimal fuss. Battery lasts 2 weeks too which is nice.
I remember researching fitbit and it just seemed like more hassle, and some features were locked behind subscriptions and stuff like that.
I would get one new enough to have QC and PD support, since most devices use one of those protocols for charging. Those really old ones that only supply 2.4A @ 5V usually can’t keep up with a modern phone.
Especially since that’s a thing that almost every MMORPG does too.