Some fun ones so far! But wanted to check: are custom backgrounds allowed? With the assumptions that you can't invent your own starting equipment package or your own feature. Basically the process the PHB describes when introducing backgrounds:
You might want to tweak some of the features of a background so it better fits your character or the campaign setting. To customize a background, you can replace one feature with any other one, choose any two skills, and choose a total of two tool proficiencies or languages from the sample backgrounds. You can either use the equipment package from your background or spend coin on gear as described in the Equipment section.
Usually I'd just avoid the question because backgrounds tend to be relatively minor in impact, but for a character who needs to fill every party role -- hey, every little helps.