I would like to say that a Grass / Fighting would be super cool for a Drought mon, as it resists Stealth Rock (something Sun teams hate) and prevents doubling up Fire-types (this works with Rain because Water is actually good defensive typing), not to mention it hits every other current Weather Starter SE except for itself and Ninetails, both of which set-up sun. Extra fire weakness sucks, but I'd still use that over Ninetails. It's typing would also help VS Rain, which is super common (although x4 weakness to Hurricane REALLY sucks).
As for hail, I think we would need something that isn't Ice-type but gets Ice Body / Snow Cloak anyways that can use Blizzard as a coverage move. Maybe something like a Water / Grass with Ice Body for extra health? Hell, Water / Grass with Snow Warning would be cool. I don't think it would boost Hail a lot though, but it would help it.