This answer by Jacob Vlijm is an excellent guide to those wishing to add custom keybindings en masse, via the command line.
There are limits, however, to what's accepted as a valid binding. Shift+p for example, is something that you can absolutely set a custom keybinding to, but it won't actually function. For a custom binding to qualify as valid (and so perform the command when pressed), I believe the binding needs to contain Primary (Control) and/or Alt (plus some normal key, like k). Also, I'm not certain whether a binding can be made to distinguish between left and right; I suspect it can't. I suspect there is no Shift_L or Alt_R, but I'm not certain on that, and hope to be wrong.
Is there a known alternative to dconf's key binding functionality? dconf is perfectly fine for nearly all cases and users, I expect; I'm just being difficult and so want to know.