Ganon's Up b is fine, getting back on stages should not be guaranteed. As far as throws go his grab range is something that should seriously be looked at. Because of his height he has a problem with grabbing and jabbing the short characters, as well as his range being based off Captain Falcons. Works for Doug because he has great speed, Ganonpork, not as much.
I think everyone agrees about his grab range, and you brought up a good point since he is a clone of CF he got stuck with the short grab range and although it works for CF it doesn't work for Ganon. Also his Jab does miss short Characters that should probably be looked at as well.
Also the PMBR should take a look at his smashes, because they were designed for a fast character like CF they have short range and don't have large hitboxes, they work great for CF but Ganon not so much especially Down smash. Since Ganon is so slow I think an increase in coverage/hitboxes on his smashes should be implemented and also redesigned to be more unique (look at one of my earlier posts for ideas).
Also can someone explain to me why Fox's Up smash has more KO power, speed and better coverge than any of Ganon's smashes? It just boggles my mind... Speed I understand but KO power and a better hitbox... I'm not saying nerf Fox I just think Ganon needs a buff in that area especially since he hold the Triforce of Power I except him to have the strongest or one of the strongest smashes in the game.
I totally agree a recovery shouldn't be guaranteed but Ike has armor on his Up B and it's perfectly fine, also Bowser has Great hitboxes on his Up B so it protects him well (idk if he has any type of armor on it though) so I don't think its unreasonable for either armor or some type of persistent hitbox (perhaps a darkness aura?) around Ganon to help protect him while recovering, he is a big and slow target I think it's only fair.