To be fair, the shield was changed very recently, however I have some slight changes to suggest.
1. Functionality Changes
Shields now have a sort of HP bar instead of just a number of hits. Shields would have 1k-2k HP and would receive 1.5x damage from melee weapons. (maybe even heal slowly over time?)
This means that stronger weapons would break shields easier, and hopefully make them less OP
2. Visual Changes
When damaged, shields will slowly start to crack, and eventually shatter upon being broken. (similar to butt-jo)
3. Other Changes
Shields now deal more knockback the faster you're moving and when moving fast enough could even do damage. (extra knockback and damage only apply when shield is being held so you can't just throw it at people.)