Number of BA's are not important, how they are tuned is what matters.
As for EM32 or EM6, it is up to your preferences. EM32 is more accurate apparently, tuned for more stage musicians with forward sounding. EM6, apparently, more colored and laid back, tuned for musical enjoyment instead of pinpoint accuracy. What I understood, EM6 can be improved version of SM64 but at the end you decide what to choose for.
I am sure Rollk can help better as he has both of them. My experience with him was nothing but pleasure, he is by far one of the most helpful users in here, if you were not joking, I would really expect you to talk nicely in the forum.
I also use only a 5BA ciem, but it blows everything else so far, I can assure you, people who knows about these things will tell you, more drivers don't mean better sound in ciems.