as far as the Hea-Hack Gun goes, I can say these things:
-as far as lights, the very first catalog explicitly said it would only have sounds, and I don't blame them. as far as the toy goes, I can pretty much tell that all the electronics are housed in the front part, so what with the wiring, circuitry, battery compartment, and Switch Socket, I don't think there's actually any room for lights in there, and all this is because of the design.
-and size-wise, come on, it's Bandai we're talking about, they always downsize because the toys are for kids, so yeah, something like this is bound to be somewhat on the small side. and considering the size of the gun compared to the switch, that should've been an indicator at the size of it
I personally still think the Hea-Hack Gun is awesome, and I've already ordered one