Spiked Shields

Don't know if anyone has floated this idea in the past, but how about having spiked shield variants? of course you can already shield bash, but the current shields are still primarily defence-only.
It's more for flavour than any real need, so it's up to the devs if they like it. It gives shield users the option to be more offensive-minded by switching shields should they need more attack than defence for a particular fight.

Spiked shields would confer less defence but cause more damage. They can also have slightly faster movement and less weight than regular shields(maybe just a 0.1 or 0.5), as shield thickness/material used is reduce for more manoeuvrability and to compensate for the added weight of sharp spiky bits, hence the decrease to blocking power.

small shield - spiked buckler: a single large spike from the buckler face, cause more piercing damage when used to bash/jab someone.
medium shield - spiked Kite/heater shield: like the current kite shield, but a round shield with more pronounced spikes all around as well as on the shield face. Might have a tribal look with furs/bones/leather straps used to secure everything and yet not have it become too heavy to be unwieldy.
large shield - no need for large-sized spike shields. A shield this size is meant for defence only, it would be too impractical to attack with a big-ass wall shield even in a fantasy setting.

the damage potential could be greater for the smaller buckler than the medium shield, or you can just increase the attack power/damage for the same amount of defence power lost.

Depending on how balance goes, you can also give the option that a spiked shield will be more likely to break or get damaged in battle, losing further defence power after some taking some heavy hits. You can do this either by reducing it's defence power after every hit, or simply allow it to take a fixed number of hits(or last a fixed number of rounds) before it becomes damaged/useless or breaks(in the case of spiked bucklers). So those going with spike shields will either have to foot larger repair bills for shields destroyed, or pay with the risk of losing the defence bonus of a shield for the advantage of having a shield that's also a 2nd weapon at the same time.