He did get more cocky. Gohan was a cocky little shit against regular Evil Boo, and it showed through Gohan-Boo. It's stupid to think Boo was better off without Gohan.
He did get somewhat more cocky but definitely nowhere near some people think he did.
And no, he's not more cocky than Gotenks-Boo. Tbf, Gotenks-Boo wasn't even that cocky. He was just sadistic and cunning.