You can never have enough Bair with GaW, however he does have so many other useful attacks that you can use to mix-up as Bair is punishable when predicted. Nair (fishbowl) is AMAZING if the opponent's are slightly above you or on large/heavy characters, also a good option to follow up out of UpB. If they are too far above you, spam Uair - hitting with the windbox (which extends vertically up the screen) refreshes your move IIRC. Dair as well is good as you can control horizontal momentum easily to make the move safer yada yada yada... Pretty much all of GaW moves are amazing, it's just about mixing them up
Trav knows more about GaW than me though, so his advice would be more credible
Trav knows more about GaW than me though, so his advice would be more credible