Chaosmancer
Legend
Cordoning them off to be a master of one of three trades goes against the spirit of them being a jack of them all. The bard to me is a character who ignores the boring lecture about the grand taxonomy of magical types and just picks up the smattering of spells that suits his needs.
Which is exactly what this bard does?
They aren't masters of divine magic. They don't get the smite spells, lay on hands, channel divinity or the ability to change their spells every long rest. They have just picked up a handful of divine spells that are useful to their needs. And many of these spells are cross-disciplinary anyways. Detect Magic is on all three lists, Purify Food and Drink is primal/divine. Thunderwave is arcane/primal.
They spend 10 levels dabbling in one of the pools, then figure out that all three pools are connected and become a true jack of all magic. And instead you want them to have a bard list that is the only list bard's can have, that is limited to bards, because that is somehow more transgressive and unique than starting with a completely different spell list than the bard sitting next to you, and eventually learning how to access all of magic? A bard spell list is a TERRIBLE way to represent what you want, and the only way this could be a better version was if they could access all the lists sooner, which I think would be a bit too much.
(Note: Huh. Enhance Ability is primal only now. Didn't notice that before)
Interesting take. A good historian should also be multidisciplinary.
And these bards are the ultimate in being multidisciplinary, just not from level 1.