Sounds reasonable. After all, multi turret tanks were based on a reasonable premise that happened to be flawed [1].Is it bad that my evolving reaction to the, "Make SPAA more relevant" discussion is the following?
If SPAA didn't help as much as desired in the assigned role, what do you do with similar armaments, even if you have to expand/accept other base models?
If we're discussing alternate timelines, why not consider an ATL where a connected mathematician speaks up in time to shift a change in hull production orders?
From there, say we get hit-and-fade heavy tankettes with a Bofors 40mm & a .50cal in the turret, plus another MG in the bow. Crew of four: driver, radio operator/bow gunner, loader/gunner, & commander gunner. You could & should mix in another type with a higher caliber/low velocity round instead of the Bofors.
The theory would be hit and fade disruption. Something produced because certain lessons were learned in the wrong order, made it to operations in the field, and it'd be up to the author to see how such an idea would play out.
TL;DR, Something that could plausibly happen but not necessarily be successful, only noteworthy.
It sounds like your system is more along the lines of a deliberate DP system right from the start rather than " let's try pointing this at ground targets since there's no aircraft around" and finding it works. This then develops into anti ground roles with little or no thought to AA function. Just needs a goodcexperience or two at a critical moment.
[1] see also tank destroyers, for a good idea that wasn't often useful as intended, but was still much better than a towed AT gun.