As a limiting factor I'd have them get built from the repair pad, so you need to shell out on that before you can build them. You can also still build them after the VF is destroyed (seeing as it's such an easy and favoured target) Oh and it would help make forward bases easier seeing as you usually drop a rep pad behind the front (on canyon at least) for your tanks.
i like the idea of the research and the repair pad being the place where their built, makes it more useful in the game and the vf less of a favored target. another list should be made of whats liked and disliked so far about the idea so everyone does'nt have to shift threw 6 pages of suggestions,ideas and debates.
well I dont rember what liked and not liked but here is a general summary: Repair droids are a ressearchable upgrade; Electrical Engineering: Mobal Reapair Tools(Increases the RepBot population to 1 from 0) Improved Transmitors(Increases the RepBot population from 1 to 3) Improved Recivers(Increases the RepBot population from 3 to 5) The ressearch times are fairly short, getting a bit longer with each "Population Increase" They are extreamly weak un-armed Bots (Possibly hovering, hasnt been decided yet) They build 2 times slower then an engineer, but do not run out of "ammo" They are controlled and built ONLY by the commander, out of a VF, or a repair pad.
Update: Repair droids are a ressearchable upgrade; Electrical Engineering: Mobal Reapair Tools(Increases the RepBot population to 1 from 0) Improved Transmitors(Increases the RepBot population from 1 to 3) Improved Recivers(Increases the RepBot population from 3 to 5) The ressearch times are fairly short, getting a bit longer with each "Population Increase" They are extreamly weak un-armed Bots (Hover, to ease pathfinding; think of HL2's manhax) They build 2 times slower then an engineer, but do not run out of "ammo", if there are damaged/unbuilt buildings in the area, the reapair droid wil repair/build those buildings until told to do something else by the comander. They are controlled and built ONLY by the commander, out of a VF, or a repair pad.