It seems like you've got a lot to learn. Which is perfectly fine of course, but after five broken bows, you want to gain some confidence and just build a bow that lasts. And I'm sorry to say this, but a 56" osage character stave that you want to heat bend into a reflex or five-curve design is a very poor choice in that respect. You're just making it far too complicated on yourself. And for what reason? Ditch the heat bending and just build a straight bow. And why only 56" with a stiff handle? I know you're going for a low draw length, but you're making a highly stressed shortbow now! Go for a bendy handle with that length, or (my advise) go for a 64" bow. Sure, 56" can be done. But gosh, you're making it hard for yourself! Keep it simple, stupid.