Just wait another gen or two when fusions become a regular thing and not just for the one legendary.
God forbid. I always hated the forms, they just don't seem to fit. If not enough, Kyurem fusions made me way more afraid of them than before.
Things are hard for Gamefreak.
The pokémon universe is very simple. Mega evolution felt Digimonesque for many because both the concept and the designs didn't fit the simple and organic feeling that is characteristic of Pokémon. I feel forms go in the same direction (Shaymin sky form with its "cool" Sonic-like vibe is one of the things I hate the most in pokémon).
Problem is, if Gamefreak doesn't add those kind of things, it will be really hard to keep the battle style fresh after decades. They can't add new types each generation and new kinds of battles (like triple, aerial) doesn't seem to affect the metagame because they tend to be ignored by players.