I know you mentioned not adding many explosives, but one that would make sense would be an upgrade to the nuke: the thermonuke since you currently have lithium and deuterium, as well as the existing depleted uranium, combining those, along with a beryllium neutron reflector would make a nice way to increase the power of the nuke by a considerable factor
just another random idea of mine.
The H-bomb is a thermonuke
Edit: You would need hydrogen to fuse, but it all would make sense to implement it into the game, considering gregtech adds all the materials necessary