If you'd like, you can check out this mod to an older version of NESpire: https://github.com/tangrs/nespire-tangrs-mod

This modifies controls a bit, not necessarily to what you want, but if you're right-handed it's a fairly comfortable configuration. It also addresses the issue of save states

But that being said, I'd definitely like to figure out what's up with the control issues. Directional input stops working, but attempting to exit freezes the calculator and forces you to reboot, yeah? The same has happened to me more times than I can count, making it very frustrating to play games which require constant input or RPGs where you can save, but not from the on-screen menu.