Ok, so I'm gonna start the thread with my thoughts (bear with me, my mind wanders and I can be a bit abrasive). Please note that this is written in a way that is intended to be humorous.
First of all... five second cooldown on my primary damage mitigation tool? Really? It's bad enough that it eats into the resource pool that I need to use to quickly move from threat to threat to eliminate ranged targets that can chew me to pieces in short order, to add a five second cooldown just makes it somewhat extraneous. My suggestion, remove the cooldown and keep the cost; or remove the cost and keep the cooldown while adding a higher than four percent chance to block ranged attacks (I'm behind a tower shield, hipfired full automatic spray from twenty meters will not find the half inch of flesh I have exposed, trust me... hipfired auto is rather hard to control). Why this is an issue? I was discussing the state of the alpha with a friend and explaining why I'm not too keen on melee and I used the following as an example:
Six cultists with rifles, one cultist with a heavy stubber, and then perhaps a dozen melee cultists (they die before they get into range so I rarely count them as a threat). A ten, maybe fifteen second fight. In that time, I soaked enough damage to remove the entire void shield stack (at 4,000 HP) and dipped into about ten percent of my base HP (which is just shy of 5k now). That's moving between two small blobs of infantry. Now, expand that to larger rooms where I'm facing three or four times that number of squishies, add in a few Traitor Legionnaires, and a stationary turret. I wipe at least once, using all the mitigation factors I currently have at my disposal, before being able to clear the room. It's frustrating early game.
My suggestion is to either give shields a high (relatively speaking) damage reduction naturally, on top of whatever potential enchant chance grants, or have shields start with a decently high chance to block per attack like other ARPGs have. I can't honestly remember the last ARPG I've played where even a third level sword and board character had a less than 20% chance to block naturally (generally 15% on shield and a native class passive of +5%), before any enchanting/gem socketing/component additions were factored in. This will, in turn, make large groups feel like less of a slog. There's no need to give us a 99% chance to avoid damage, but definitely account for the fact that we're spending most of our time footslogging into the crush of battle and absorbing prodigious amounts of fire that ranged characters are mitigating via cover. In fact, treat it like cover... don't protect us from all sides, but for the love of the Emperor give us some better coverage.
I bring this up because after some discussion in-game, it looks like outside of the community's resident master builder (the gent that managed to clear 30 minutes in the Cathedral), almost nobody actually bothers with a shield. Great weapons, or melee and pistol. That's a crying shame, considering how useful shields are in both the tabletop/pen and paper RPG crunch, and the lore. Give us a good reason to give up that extra DPS.