Heracross is both visually appealing as well as interesting to use. It has always been rare, yes, but so has Pinsir, and Heracross has always given you more in return for finding it. It has great stats, a great movepool and is an all around good contributor to your team. Pinsir is, well, Pinsir. Slightly underwhelming, boring movepool, and while it looks iconic, can't stand up to the blue beetle.