Alternative: how about a boat that can build LABs directly on shore? Kind of like how the Megalith has "crab eggs"
Maybe the "engineering ship" can build a very small "tiny factory" (the size of a t1 pgen or slightly larger) that can produce nothing but LABs. Or nothing but LABs and land scouts. And these factories have very little BP so they work best with an "engineering ship" assisting them, that way you can't really run an invasion by having your engineering ship make 20 mini-facs and driving away. Each engineering ship would make 1 mini-fac and then assist it and the result would be LAB spam from the water.
Maybe regular engies should also be able to build/assist this so you could turn an engie drop into LAB spam without needing to build an entire t1 land factory. It would be a new way to make raids happen faster, so LABs get more use.