Which rules would a sovereign UK be "bound" to?
You're not doing a version of the pro-EU myth that countries like Norway "have to" comply with EU regulations despite not being having any control over them are you?
The truth is of course Norway don't "have" to do anything, they choose to opt in to certain EU agreements in exchange for trade deals and can out of them should the Norwegian people want to (unlike us at the moment).
Furthermore, to think a country with an economy the size of UK would have no affect of how the EU comes up with rules is asinine, we may not 'be at the table' but how the UK reacts to any new legislation will always be 'on the table' regardless of whether we are in or out of the EU.
The USA and China aren't in the EU but do you honestly think they have no sway over it? No we are not as big as those countries and never will be but we are big enough to influence anyone.