Most of Haman's Children - A Maoz Tzur Thought

For many years I've been wondering about one line of the famous Hanukah song:

רֹב בָּנָיו וְקִנְיָנָיו עַל הָעֵץ תָּלִיתָ 

This is a verse dealing with Haman - and praising the killing of his sons. However if you asked most people what the verse means they would translate it as "Most of his children and his property you hanged on the tree." What has always bugged me, is why do we say only "Most" and not all?

I think there are two answers, one of which is Yeshivish and one of them true.

The yeshivish answer would tell you that somewhere in Masechet Megilla (Talmudic tractate) it says that Haman had many children (some 200 if I remember correctly) other than the famous ten who got hanged. However this answer has a fatal flaw - if we are counting 200 children, then clearly 10 isn't "Most" of his children.

What I think the real answer is that in biblical Hebrew, the word רב instead of meaning MOST means ALL or Many. One good example comes to mind - from the book of Esther:

כי מרדכי היהודי משנה למלך אחשורוש וגדול ליהודים ורצוי לרב אחיו דרש טוב לעמו ודבר שלום לכל זרעו 

(Esther 10:3)

In this Pasuk clearly רב = all or many -  despite the many sermons you hear about it during Purim.