I would guess that a plastics range will be far more limited in the numbers of ship designs out there, only two or three types of ships for each race tops, possibly just the ships seen in the series. That way they would only need to produce a few of the expensive molds.
Would mean the game would be much more like the series, with the ships being used being the iconic ships of each fleet, but would radically change the game.
On that basis, I'd much prefer remaining with metal figures, where it is possible to create a mold for a small production run of obscure figures.
I could be wrong about the above though.
Oh, another thought. With a change of scale to something closer to the 'fleet action' scale some people speak of, you could have a complete range of ships for a fleet on a single spru. That would make things much more doable perhaps.