Re: Almost bought a QL
"Presumably Motorola based their 68K instruction set on the VAX"
Don't think so. There's lots of differences between 68K and VAX at a fundamental level, eg. on VAX most registers can be used for most purposes, not so easy on the 68K.
If you want a look at what a modernised re-imagined VAX instruction set might have looked like, try the NatSemi 16000/32000 family. But you might have to look quite hard for any relics of the day,