There have been more than a few alternatives suggested (return to Saving Throws, percentile resist, etc), but the overarching trend that I've seen isn't that the Armor System is objectively bad, it's that its implementation is painfully bland, incredibly unpolished and restrictive, and had next to nothing built into and around it to make it interesting to anyone but people who are sated by the CC-Chaining being delayed a single round of combat.
The vast majority doesn't want a specific system, they just want literally anything else, even a better integrated iteration of the current system.
