A modernized Hetzer probably could be slung under a helicopter, and certainly issues like visibility and crew ergonomics (the interior of a Hetzer fit the crew like a shirt) could also be addressed in a reboot.
It is small enough to slip down black tracks and show up in unexpected places, and allied tankers were quite wary once it was discovered these were in the area since they could be hidden away and camouflaged virtually anywhere (for scale, look at the pictures again and compare the size of the Hetzer or its Swiss counterpart to the people on and around it.)
Overall, if I was to make a choice between a monstrous "Chimera" and an SUV sized tank destroyer, I'd favour the smaller vehicle.