We need more "boom" in this game.
1) Make it so that whenever an explosive barrel goes off it breaks any barrels that might be next to it, not just objects. Also, make random barrels of larger sizes that have a greater effect and AoE.
2) New spell for artificers: "Retributive Explosion". The target gets the "Explosive Potential" buff. When the target dies, everything around it in a standard AoE takes 5d10 + 1d10 per 6 caster levels, where half is fire and the other half is force. This spell can only be applied to friendly constructs, living constructs and undead because the druids threatened to sue.
3) We need an update to the trapmaking system so that grenades of different elements and types can be made more easily.