Geeze Gosshawks are the queen of all forest hunting birds!
Harpy Eagles are used to hunting in forest situations though, they hunt in their native jungles!
But Harpy Eagles have taken out deer before... Which makes them incredibly useful for a hunter. While the Harpy Eagle hunts one thing the Endal another and their wind Eagle hunts something else! That's at least three things down, unless the hunter or the Harpy Eagle requires help from the other.
So if you want to be a good hunter go for the Harpy Eagle, a good warning system or lookout Peregrine falcon all the way, something that can navigate even the toughest of forest's Gosshawk.
Whichever hunting bird calls to you. Don't go with something you don't feel fully great about, it'll show in your posts.