To my knowledge currently all the effective builds don’t make use of shields. Everything is stack IAS,CC,CD,LS,LOH. The most effective D3 strategy is offense is the best defence.
The 3 main points I see as limiting a shields use are.
1. Block damage figure being so small, especially when you play high MP and it’s totally possible for you to take 10s of thousands of damage in one hit.
2. Block % chance being low
3. No effective skills that make use of equipping a shield.
4. Dual wield being too effective
I don’t want to harp on about how it was in diablo 2 but shields were useful, actually in allot of cases on high difficulty a requirement. My preference if Blizzard did in future change this would be for a happy medium to be beneficial if you want to change your play style to incorporate them.
A few suggestions to potentially help with my above points.
1. Block damage figure have a dynamic element. E.g. variable base block + extra figure based on strength (include cap based on class)
2. Block chance figure have a dynamic element. E.g. variable base chance + extra figure based on dexterity (include cap based on class)
3. Open to suggestions on how but some skills to allow for some crowd control while using a shield. Without adding more skills I’m sure there are plenty of under used skills/runs from all classes which could be changed as appropriate.
4. dont nerf it but make other things as effective
I feel if something like the above could be achieved it would be a step in the right direction to move away from IAS,CC,CD being the only way to build an effective toon.