The 75k number for Kuririn works fine, considering the questionable accuracy of Vegeta's estimation and Gohan not knowing about Freeza's transformations when agreeing they might manage something. Meanwhile, the closest thing we have to defining evidence on Piccolo's power is El Manga Legendario stating he got a 5x boost from Nail to place him significantly above 200k. Questionable, but still better than nothing. That said, Piccolo stomps.