This is a homebrew question;

How do/should grenade weapons work?

I'm working on an alchemist class, and I want a good universal mechanic for throwing bombs and vials and stuff.

Right now I'm leaning towards: when you throw a grenade weapon, make an attack roll. Creatures within the AoE make a reflex saving throw for half damage against the DC set by your attack roll. On a roll of 1, the grenade is lost with no effect.