Your instinct is correct i.e. we will NEVER agree what is kink and what is not. Some girls think me swatting them on the ass lightly with a flogger is wildly kinky, as they may have never done it before, while others think that is vanilla as vanilla gets.
One persons "open mind" about BBBJ is them demanding you give them fair warning BEFORE you jizz as no cum will EVER get into their mouth, while other "open minded" women will slowly, and very willingly, take it all in, savor it, show it to you, then swallow.
So I can't give you definitions on these things as these terms are just so vague. "Kink" or "BDSM" or whatever term you want to use, is such a wide and varied part of p4p that it needs TONS of more communication beforehand than a standard GFE type date, for example.
All of that communication is desperately needed due directly to the fact that so many have so many differing opinions on what "kink" is, and what it is not.
The critical thing is you HAVE to be on the same page as your partner, as it is imperative that you two agree on the definitions, and not be concerned with how anybody else defines it.