Mudbunny, that looks good to me. Kobold Stew is right, go with the Calligraphy tools proficiency. Abyssal is fine. Draconic, for campaign reasons, is not (dragons are myth and legend to the uneducated and ancient history to the educated).
Okee dokee. I will write it up this weekend and post it when you get up a rogue's gallery post.
All, if you want to establish connectivity to future characters, here are a few other options...
2. Same Order - Each character is a member of an organization or group. The Church of the Healing Light is a good option here, as is a demon cult, bard college, or a knightly order.
I will be grabbing this one. My characters will all end up swearing an oath of some sort to the same demon.