I've gotta say, apart from the theory I have never noticed anything feeling harmful like that from any 2C I've tried (B,C,D,E,I,T-7), while basically all stim empathogens I've tried seem to say: you're within limits with these doses but don't overdo it!
Having said that, thing you could do to make the load heavier (so avoid these) is insufflating significant doses of especially the harder 2C-Xs. From easy to hard I would list them
2C-C < 2C-D < 2C-B < 2C-I = 2C-E < 2C-T-2 < 2C-T-7 (the 2C-T-2 is only my suspicion and 2C-I seems a little more empath stim like at some points while 2C-E can have mighty psychosomatic effects).
I don't really care whether it's MAOI, some kind of cardiovascular or cerebral load or higher levels of 5-HT2 agonism or a combination of these - well I do care but not when the message is the harder 2C-X you take the more careful your approach and ROA should be!!!
That is not to say you shouldn't always be careful but you know what I mean.