Given that so much of our history (the history of people genetically indistinct from us) was unrecorded and presumed to be some form of hunting and gathering where no innovation took place (that was recorded), I think it goes too far to call innovation a human universal trait. I wish we could know what human cultures were like prior to all recorded history, even thirty thousand years ago. Perhaps we innovated in oral traditions, art, cooking, animal handling, social customs (you can innovate e.g. slang), dance etc. That would convince me of innovation's place as a part of human nature. Short of that, I think of it as more of an occasional capacity or potential, and something we can find rewarding. Dogs can learn a great deal of clever tricks that they enjoy doing, but you wouldn't call it canine nature to play dead when shot with a finger gun. It's a novel behaviour borne of circumstances that can become rewarding with gradual behaviour shaping processes. I think of things like human invention as basically the same process with a more complex brain.