Primeape is a joke. And Ash had reasons to release Lapras, Butterfree, and Pidgeot. Not saying Butterfree and Pidgeot were weak Pokemon, but Ash has stronger Pokemon in his arsenal, although I wish he had gone back to visit Pidgeot (and possibly Lapras and Butterfree as well) like he promised
I wonder why no one mentioned Lapras in these type of threads. Lapras could easily becoming Ash's strongest pokemon given the opportunity. It's base stats is higher than of Blastoise, swampert, and Feraligator.
Ash saw Lapras again in Johto BTW.