Okay - perspective from someone who is not, and won't be an expert (of whom "normal" difficuly, for example, is the maximum difficulty of any game played, and "easy" is more common).
Yeah it'll make the mech beastly, but nobody will shoot at it. The AI will just ignore it in favour of a better target, as will human players in multiplayer...
Unless they change the AI and give the bulwarked mech some sort of "aggro" or "taunt" mechanic, it will just be a pointless ability in the campaign.
Yeah. I used brace outside of combat
maybe twice in a hundred hours and I never used the ability (I can't even remember what it is called); nor am I ever likely to start. Trading migitating damage for not shooting might maybe be situationally okay in multiplayer (I don't multiplayer), but against the OpFor when your out-numbered, you need to be defeating in detail and as fast as possible and you can't do that by not shooting. Every round you are not shooting the enemy is a round you haven't killed something.
Shooting AI with it on is basically a waste of anything with ammunition. At 75% damage reduction (the AI does use cover, after all), you might as well write "don't bother" instead unless you have breaching shot. (I suppose at that point, you might as well brace, and I can see the really exciting scenario of when down to the last mechs, you and AI sitting around bracing, because neither of you will be the first to attack... Shades of Ash Ketchum's first battle with Caterpie in Pokémon.) You don't have usually enough ammunition when you have to deal with eight to twelve enemies that you can afford to waste it on something that it will barely touch.
It might work using a decoy for the AI to shoot... As long as the AI is programmed to essentially waste its round actually shooting something at 75% damage reduction, which is not good strategy if you have other targets. (And one would suspect that as BT goes along, the AI will get better.)
Combined with new accuracy debuff issues with sensor lock when dealing with loads of OpFor (which has the number if can spare to debuff you, like you can't afford to unless you can't do anything else), we have basically lost a major method of migitating damage AND will now lose accuracy. Evasion doesn't grant you enough late-game when you have all assaults, fighting all assaults. (my Atlas spent the entire game jumping around for evasion and evasion did almost nothing to help it, even with an evasive pilot) Three chevrons if you jump is the best I found I could managed and that made very little difference to the OpFor. (And the new changes encourage sensor lock, too.)
All of which is going to make the game much harder when outnumbered. And honestly, unlike a lot of the fine folk around here, I don't want the game to be (
non-optionally) harder, the difficulty was fine where it was - for me.
If this change persists to Flashpoint, I would suspect I will simply drop bulwark completely and all my pilots would end up, like as not, using some mix of gunnery and tactics skills (I didn't think all that much of piloting before, so most likely will replace bulwark with sensor lock. So less variety than before.)
And I say that, because, my feedback, I'm afraid, has to be that I am going to pass on testing this new beta myself. I've had about enough BT for the moment doing the campaign[1] and I really don't fancy trying to fight eight or twelve to one odds now that not only have my defences been reduced, but my offense lkely to be as well in a fair number of missions - it's not revitalising my desire to play more at the moment, I'm afraid. I will cross that bridge when Flashpoint comes out, if necessary.
(When I can get all the by-then- experts to tell me what the best alternative in the current meta is.)
*tips helmet to HBS staff*
[1]I switch between games a lot, and I don't generally play one game for weeks on end. Wicther 3, I think, currently holds the record when I played it for the first time this year, for holding my interest for 215 hours without my taking a break to play something else in the middle. At 130 hours with only one day playing something else, BT has already done well.