While I agree with you that considering disablities val and var maybe aren’t the best choice and something else might have been better this can’t really be changed since kotlin is stable. Maybe in a 2.0 release, but even that might be impossible.
Also there is a really long topic about this (with pretty much the same arguments as yours) here.
I suggest reading through it, maybe you have some more points to add. People suggested adjusting your IDE settings to highlight the difference between val and var in the code more. Not sure about the key strokes but I this should be possible with live templates. Just create them for val and var. If you call them v(var) and l(val) or whatever you can just type v to expand var and l and expand to val.