"So should he look that seems to speak great things."
Collier's folio, I think rightly, reads comes for 'seems' (see on All's Well, ii. 3). We can hardly take 'to speak' in the sense of about to speak.
"From Fife, great king, where the Norweyan banners
Did flout the air, and fan our people cold.
Norway himself with terrible numbers there."
Both sense and metre require Did. The battle was over, and the enemy defeated.