Once all of those attacking creatures are assigned lethal damage, any excess damage is assigned as its controller chooses among those attacking creatures and their controllers
As most of your mages have enter the battlefield effects, these will cause them to trigger again twice if Naban is present
Yes, its no surprise if Gandalf is coming from your command zone, but the additional flicker trigger is massive, well supported in white, and a worthy ability of a wizard that needed to evolve to compete with Saruman
Standard players who dont want to be playing against the same black midrange decks for another year are hoping Wilds can offer even a couple of cards on the level of Bonecrusher Giant, Brazen Borrower and Lovestruck Beast
Different identities should have crazily-strong cards
Release timing is everything