Some good ideas there.
However, in 20 years of using a Psion 5mx (including in bed most nights, with the lights off, and you can stop sniggering at the back), I've never felt any need for a keyboard backlight. The keyboard has so few extra keys that there's little chance for confusion, and if you do much typing with it, you come to feel where all the keys are (whether in two-thumb or full touch-type mode).
Similarly, I never need to resort to a stylus; most of what I do is via the keyboard, and I find that a fingernail's plenty accurate enough for the screen. (I just turn or bend my index finger slightly.) A stylus would give slightly greater precision and visibility, of course, but Psion apps don't require infinite precision, and a fingernail's much more convenient.
So those are two things that might not be quite so important after all!
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This has reminded me that at one point, Psion themselves asked for ideas for a successor to the 5mx. I can't recall everything I suggested, but it certainly included a colour screen, headphone socket, stereo audio, more storage, and probably Bluetooth and/or USB, faster processor, thinner/lighter — all of which the Gemini has! And much more besides. So we are (about to be) living in good times.
