Atm, there's almost no reason to use riot gear shield, due to absolute inferiority compared to Spear. It's also losing against Parry, which imo much better due to Dex scaling and works with any armor, also it works with swapping weapon, regardless of melee skills, which makes the blocking mechanic accessible to all type of weapon instead of just 1-handed
My idea to buff riot Shield (and hopefully doesn't translate to nerfing all other blocking source) is :
1. Add ranged attack blocking, which makes riot Shield much better and special compared to other block source
2. Removes 2-handed weapon restriction (could be tied with current feat such as Arm Shield, new feat, only accessible with certain shield type, or by default)
3. Adds "reflect melee damage" (either from additional mod using Spiked/serrated, Feat, or by default) alongside with blocking, which enables high CON turtle build around it
Any other idea is welcomed