I don't think Hannah will ever become a legit stretch 4. While Gustafson has stretched her game out to the 3 pt line, she started with a solid elbow jumper and always had a decent FT stroke (81% as a junior)...Hannah doesn't have either of those (much improved from FT, but still only 69% as a junior).
Hannah needs to double down on her strengths. She is okay around the basket due to her strength and quickness, but she lacks craft. She takes too many dribbles, and if she doesn't get a shoulder past her defender on her initial move, everyone knows she is spinning back, and then guards are ready to dig down and steal, or posts just play straight up and stymie her with length and position. I don't know if anyone keeps track of how many times a player's shot is blocked, but Hannah might lead the nation.
Lucy is a great example of what craft can do for you around the basket. She can spin both directions, step through, scoop, fade, or hit off-balance leaners. Czinano had a lot of these tricks. Even Addy has a good toolbox to pair with her size, she shoots jump hooks over either shoulder and she has a little fade away. Hannah just hasn't built the same toolbox, or at least she is not as good at deploying it in games.
The perfect comp for what Hannah could become is
Aneesah Morrow (projected to be a top 5 draft pick). She is an undersized post who is not a great shooter. But she is a dynamite scorer because she has excellent ball-handling skills, and she can finish over, under, and around people at the basket.
I sometimes wonder if part of Hannah's slow development comes from Jan trying to coach her the same way she coached Megan and Monica? So, she is becoming a worse version of those 2 (offensively), as opposed to an awesome version of herself. Probably nothing to that, just something I think about.