I think this could be an interesting concept if implemented right. It could be a bleedthrough effect block, which you can slave into a weapon system, which at 1/1/1 ratio would provide 10% bleedthrough. This could actually make heavy armor useful. Because, say, if it reduces damage done by 50%, then the result will be the following:
A cannon that deals 100 damage hits the shield, 10 of that damage penetrates the shield and hits the armor block, damage is then halved due to armor block. 5 damage to a hardened hull block is nothing serious, but it gives the smaller fighters a chance to fight, rather than not having any chance against impenetrable wall of shields. Once you penetrate that hard hull, your damage will double on regular blocks. But I guess large ship maneuverability needs to get more nerfs so that it's even possible to hit the same block twice.
Then again, a large ship hitting for 10000 with its cannon will obviously one shot any block through bleedthrough, which is bad. I guess bleedthrough damage can be capped at like 20 damage per shot?
My favorite thing about this game is building humongous battleships, and I think that would be a good idea for balance.