This is something I was thinking about for a long time:
I think that there should be some strategic purpose for C4 or Dynamite, other than just blowing up other players.
So I think there should be something like "cracked walls". Cracked wall is a piece of wall that can be blown up only with c4/dynamite, and it would open new entrance to a building.
Here's example (placing of the cracked walls is totally random):
So if your team has C4, it can use it in strategic way, to get to a building with another way.
There could be ALOT of places where such "crack" can be put and make the thing more interesting [broken hills FLC or Gecko Reactors for example].
After some time the blown up wall would respawn (maybe with a help of an NPC, similar to Grave Keeper.