I have a bunch of devices. Steam Deck, Miyoo Mini, Retroid Pocket 3+, Analogue Pocket, modded 3DS, and various modded Gameboys.
For most retro games, I find myself reaching for the RP3+ the most. Don't get me wrong, all the other devices are great too, but it's a great size and works without fuss up through PSP.
And for value/$, it's hard to go wrong with any of the trending emulation devices, be it from Anbernic, Miyoo, or Retroid.
Retroid and the newer Anbernic devices running Android don't appeal to me as much personally. I really like the charm of a dedicated Linux OS. Just something about connecting my Google account that really kills it for me.
Aside from that, retroid makes pretty solid devices too from what I understand.
The interface on the Miyoo Mini (with OnionOS) is a lot smoother and more streamlined than anything with Android. I definitely like how easily you can switch between all your recently played games so quickly, regardless of system.
Android devices tend to be a bit more flexible/powerful with more emulator options, but the interface isn't as complete and more tweaking is needed. It's not perfect, but I'm enjoying Diajisho.
It seems pretty common to use a different Google account on your device than your main one. I only use it to access the Play store, then I disable all Google services until I need it again.
But there's really no right or wrong approach here, as long as you're playing games and enjoying it.
Don't the miyoo devices go in stock for like 2 minutes s couple times a month? I was checking for a while at one point and only saw it in stock once over the span of weeks.
Edit: I see that the plus it's actually a new device with a easier to source, but worse, screen. That's unfortunate.