Quoted By:
>Mega Blastoise gets its own ability
>The other two get boring abilities that other mons do better
Here's a better idea.
>Mega Charizard
>Moves with cooldown/a turn of preparation have the wasted turns nullified
Now it's actually viable on a regular sun team and can use its most powerful moves like Razor Wind to actually deal some fucking damage. Drought is useless on this because you can't rely on it for sun coverage. Your team would have to be non-weather for it to be useful. Mega Charizard should have a more aggressive ability than that, but GF was at least true to form by giving Charizard something flimsy and non-viable.
>Mega Venusaur
>Moves that debuff your opponent's stats boost your own stats the same number of levels
Grass/Poison is all about status and debilitation. Why not make stat drop moves actually useful? It plays to Venusaur's strengths without just being "more status". Thick Fat isn't a BAD choice, but it isn't new or interesting either.