Ok, I'm writing a fic about Hannah Abbott's first year at Hogwarts and I was wondering about who they could share classes with. I know there's been a lot of discussion about classes and schedules and why Gryffindor only shares 2 classes with other Houses (Herb with the Puffs and Potions with the Slyths.) This is what I came up with and I'm wanting to know what other people think:

The schedule is completely random. I've tried many times to sit down and map out Hannah's class schedule but nothing makes sense. Either they've got way too much free time or their teachers would have no time to teach other classes. So I've decided that sense Hogwarts itself is filled with magic and organized chaos then it's classes are the same. There is no obvious rhyme or reason to it.

That being said my main question is
Do you think that because Gryffindor shares potions with Slytherin that Hufflepuff has to share potions with Ravenclaw? I'm leaning toward no. I think that who they share classes with and what classes they share are somewhat random. In Ginny's year Gryffindor shares Transfiguration with Ravenclaw showing that eventhough Gyffindor's in Harry's year have the class to themselves Transfiguration is still a shareable class.

Ugh. All this thinking makes my head hurt!
In my fiction (rough rough draft at the moment) Hufflepuffs share Herbology with Gryffindor, possibly Transfiguration with Slytherins, and History of Magic or Charms with Ravenclaw. But they have potions by themselves. Is that believable or do I need to change somethings?

Any thoughts are welcome!!