I haven’t tried it myself but the Ambernic RG556 looks like a chonk and has an OLED.
On second thought it’s about the same size as the one I’ve got at 5.48” probably not enough.
Thought about using a Bluetooth controller with your tablet?
As Sramder mentioned, something like the rg556 (oled and the black levels make reading text against dark backgrounds much easier) or the Odin 2 (good quality ips and little bigger with a 6 inch screen). Other options would be something like the logitech g cloud (weak soc limiting systems, 7 inch screen).
Overall the rg556 is a great overall device with built in controls. Think the screen from an iPhone 14 turned landscape, about half an inch less wide and just a hair taller. Gives you a ballpark idea of size anyway. Hope that helps!
SBC Gaming is for Single Board Computer aimed to play video-games, also called Retro Handhelds
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