A-not-A (你去不去?) offers two answers laid out to pick from. 好嗎 hands over one proposal and asks for a single nod.
你是學生好嗎? → 你是學生嗎? (a fact takes plain 嗎, not the consent tag)
我們走吧好嗎? → 我們走,好嗎? (drop 吧; one softener, and pause before the tag)
好嗎我們走? → 我們走,好嗎? (the tag hangs at the end, never up front)
English drops the tag question onto almost any statement (you're tired, aren't you?). 好嗎 only tags a suggestion or request — never a flat statement of fact.