I got a lot of good feedback from the PSPi Compute video. The board is almost done, and I only have two remaining bugs to fix before calling it complete. I've done some power tests, and at the moment, without any underclocking or optimizing, it gets 2 1/2 hours of play time with the LCD at full brightness, and between 3 and 5 hours of play time with the LCD at minimum brightness. It can probably do even better when at idle.
https://othermod.com/pspi-compute/

The PSPi Zero boards are back in stock after selling out earlier this week. This batch is selling a bit faster than usual, probably because of the Pi Zero 2 news. Speaking of that, I have a Pi Zero 2 on the way, and it should arrive Monday or Tuesday. I've done a lot of reading, and I'm optimistic about this being mostly compatible with the PSPi Zero. I'll know for sure in a few days.
https://othermod.com/product/pspi-zero/