So if they had made one change, it would be fantastic as a throw-in-the-backpack computer.

That change would be to support display port alt-mode on a USB-C port, rather than only having mini-HDMI. If they'd done that, you could plug AR glasses like the XReal One straight into it, and not need a separate screen. Your entire compute becomes a keyboard+power, glasses, and wireless mouse. That would be really nice: two cables, total, one for power to the pi and one from the pi to the glasses.

As it is, you need an hdmi to usb-c converter, which also needs to be powered, another couple of cables, and more of a setup faff each time. It sounds minor, but it's a missed opportunity. For me it turns it from "take my money" to "eh... I can do better."