Personally, have had a hand in putting together 5 Boomerangs, and never added nose or tail weight.
My 2 Boomerangs had an Irvine 46, and an OS52 4S. And no nose or tail weight added.
The other 3 Boomerangs were 1 SC46 and 2 all electric, and no nose or tail weight added.
There is loads of room in the Boomerang to place the IC 4 cell battery where required, or the 4S Lipo, where required