Who should we please: the many or the few?

"The many speak highly of you, but have you really any grounds for satisfaction with yourself if you are the kind of person the many understand?" -Seneca
I think the core of Seneca's point here is that if you dilute your message so far that the many understand it, then you have diluted it to the point that it is so watered down that it lacks any meaning whatsoever.

Seneca's discussion of crowds and their many ills in this passage brings to mind this line from a very different source:
"You can either fit in or stand out, not both." -Seth Godin, Linchpin
In Seneca's address to Lucilius, it seems like this is what Lucilius is trying to do--stand out and fit in, which is an absurdity and an impossibility.

The choice is clear: stand out.
Make a ruckus.

Be willing for some people to not understand you and what you are about in exchange for connecting ever more deeply with the people who do understand. Who do get it. Who are your tribe.

As Seneca said earlier in the passage:
"Associate with people who are likely to improve you. Welcome those whom you are capable of improving."