Is there a rule (I am asking honestly - not trying to be snarky) by which one cannot have the series on both Tapas and Webtoon?
It seems to be Webtoons has more traffic, period. However, that would most certainly be an English-speaking community (though the Spanish-speaking community enjoys its comics very well, let me tell you - and according to my very anecdotic experience, is more engaged in communication too).
I guess I will agree with tired_programmer above and go with A), unless you can have both versions on both sites. Why not spread your comic through the web the way the 60s tried to spread love through the world?