Why not have the launchers and tunnelers as two formations, having the tunneler in strategic reserve (deploying) and then return via planetfall rules and then any units deploy like a drop pod. Basically have the launchers act like a space ship only on the board. Basically they're tanks. Put some light weapons on them and you can use them for whatever. You just need the formation to deploy them, but once they're deployed they're just useful for contesting objectives and everything else.
Nids wouldn't need the launchers, but then they wouldnt have the extra formation.
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Victory? What use is victory? Let me have a battle of annihilation.
+++ Fleet Commissar Drussos +++