Yeah but your point was the most expensive light TD. Yet the stug3 and m10 cost more. So you are wrong.
If must say...M10 and Stug3 need medium tank tech.....for balance it coming later so have 160 damage is fine,but look su76,as light TD,is coming later than OKW puma,and cost more,for now even it vet 3 it not have 160 damage so it useless in late game.
For those TD like M10 and Stug3 in late game they default 160 damage also could punch most medium tank,but don't forgot Allied without commander and UKF Comet and Churchill not have tank HP more than 640,so Allied should have more powerful TD against German heavy,but still that problem,SU76 not have enough damage to use even in VET3,even vet3 it can not beat new Stug3.