I think simply nerfing explosive packs will do little good to game's enviroment.
This decision will only make those bomberman change from throwing 27 explosive packs to throwing 27 grenade or 18 grenade +9 explosive packs or 27 cocktails or some other combination.
Thing were going well when we just throw 1 grenade/packs per soldier without range perks(+50% throwing distance)But things go wrong when they equip every soldier a Large grenade pouch and perks the throwing range(makes soldier throwing things behind many obsatcles preventing rifleman to stop them),so I think the problem is on the abuse of Large grenade pouch and the range perk ,not the explosive pack
My suggest:instead of nerfing explosive pack ,nerf range inrcreasing perksfrom+50% to+20%or25%,and set a limit to the number of Large grenade pouch equipping per squad