As you point out Mr Phase, the mecha units would receive stats to fulfill a particular role. In the gaming community its called balancing. I would assume Mechs would fill a close combat role similar to the cutlass fighter in OE3. So really what it comes down to is adding a sprite (what unit looks like on screen) that resembles a mech, and giving it roughly similar stats to the cutlass. I don't understand why you think that is such a terrible idea. At the very least it has the potential to broaden the audience.
In that case, don't buy the mecha units, sell the ones you win, and enjoy the opportunity to smash the ones you encounter in battle. Prove just how impractical they really are. It really is a no lose situation.
While I agree on principle, Sir Maxeer III, I'd point to the players who could care less about the practicality of matter but care a great deal about fielding their own personal fleet of cool mecha fighters with beam swords or whatever.
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