Star Fox Zero was even close to the end of the Wii U’s life cycle, so the gamepad wasn’t even “new” by that point. They really should have either not used the dual-screen gimmick altogether (realizing that people can really only focus on one screen at a time), better optimized their level design for its use, or where it could have actually worked was to use it only in a 2-player co-op mode where one player piloted the ship with a Wii-mote/nunchuk and the other was the “gunner” using the gamepad to shoot enemies. (I’d also allow the player with the Wii-mote a gunning option, maybe point-and-fire like shooting star bits in Mario Galaxy, or give that player control of the bombs.)
Star Fox Zero was even close to the end of the Wii U’s life cycle, so the gamepad wasn’t even “new” by that point. They really should have either not used the dual-screen gimmick altogether (realizing that people can really only focus on one screen at a time), better optimized their level design for its use, or where it could have actually worked was to use it only in a 2-player co-op mode where one player piloted the ship with a Wii-mote/nunchuk and the other was the “gunner” using the gamepad to shoot enemies. (I’d also allow the player with the Wii-mote a gunning option, maybe point-and-fire like shooting star bits in Mario Galaxy, or give that player control of the bombs.)