I once heard r' yoel farbreng, how R"H isn't a light term to throw around.
I believe it was in response to new mashpiim calling yud shvat r"h le'hiskashrus. He said that you lose sensitivity to everything when you make up new r"h for everything.
R"H isn't a celebration, it's the head, the day you get chayus for the whole year. You ave to be a Rebbe to make a day into that.
On that note, I believe it says somewhere in that shevii shel pesach is rosh hashana for mesirus nefesh, do you know where that is?