I just found a comment that I had meant to post sooner:
I never meant that being weak was per se a reason why a piece might be neglected, I was thinking more in terms of weakness combined with complexity. The Antelope is indeed in the Piececlopedia but the Fiveleaper, an Antelope compound with another colourswitching piece, is not - making it slightly puzzling that the Fiveleaper's colourbound dual the Root-50 leaper is.