If you could design your dream retro handheld, what would be non-negotiable?

Hey r/SBCGaming ​

I've been deep in the retro handheld rabbit hole for a while now — owned a few Anbernics, a Miyoo Mini Plus, a Retroid Pocket, even messed with emulation on Steam Deck. Each one nails something but none of them feel like the "complete package."

So I want to ask the community a simple question: What features do you think a perfect retro handheld absolutely must have?

• Not just specs — I mean the stuff that actually changes how you play. To kick things off, here's my own running wishlist:
• Instant sleep / quick resume — close the lid, open it back up, immediately back in the game. No reboot, no menu, no waiting. Switch and Xbox figured this out years ago and somehow most retro handhelds still don't.
• Real cloud saves across devices — start on the bus, finish on the couch. Why is this still hard?
• Auto-scraping box art + metadata out of the box, not a 30-minute Skraper session.
• Long battery life (8h+) and reverse charging would be a bonus.
• A UI that doesn't look like a Linux distro — clean, console-style launcher, with deep settings hidden one layer down for power users.
• Local multiplayer / link cable revival — 2P on one screen, or two handhelds linked like the old GBA days.

Some questions I'm genuinely curious about:

1. What's the one feature you'd give up everything else for?
2. What's a feature that sounds great in reviews but you never actually use?
3. Native screen size sweet spot? 3.5"? 4"? 5"?