I was pondering if "vanilla" should be part of the name as well. In the end I felt I got sufficiently close to the vanilla flavor you describe, and the name conveys the "as little as possible" approach. Hope it's not too misleading!
I do like the "plus" idea, now that you mention it! Will think about it :)
Vanilla JS has also been a long-time joke about how modern javascript has advanced far enough not to need libraries for a lot of stuff people still reach for: http://vanilla-js.com/
I do like the "plus" idea, now that you mention it! Will think about it :)