So I decided to write up more detailed feedback, and I'm thinking about sending it to Valve. But first, I want to get your feedback on my feedback to Valve's feedback.
Panic Attack: The Panic Attack didn't need a complete redesign. I thought the idea was neat, especially on engie, who uses the shotty as his primary instead of as a backup. Perhaps on Soldier and Pyro, who both use the shotty as a backup, it's not as used because the shotty needs to be there as a backup, but on engie, who uses it as his primary, I thought it was very viable as a surprise attack, in-your-face ambush weapon. As such, I believe that the current stats are fine for engineer, but not for other classes. Perhaps the Panic Attack could be replaced with something else on classes that use it as a secondary.
Ambassador: Although I can't say I dislike this change, I think a much better solution would be to simply have long-range damage falloff (and replace the crits with increased damage, cuz the crits will override the damage falloff). Although the idea on headshots on any class other than sniper is probably a bad idea to begin with, so it probably needs a redesign (along with the Diamondback), or a penalty that actually gives the weapon a real downside.
Dead Ringer: I've been waiting for this change for a while. I like this change.
Your Eternal Reward: I'm on the fence here. On one hand, this is kinda diluting what made the Your Eternal Reward interesting, but at the same time, it makes it slightly more viable. I absolutely suck at spy, so I don't think I have the experience to confidently say if the allowing disguising at the cost of cloak mechanic is okay. The only change I do suggest (if they do implement this) is that they make it so that ammo doesn't recharge cloak for about 8-10 seconds after manually disguising, so that players can't disguise and immediately pick up an ammo pack to refill their cloak and negate the downside.
Sandman: I have no problems with this, except for the decreased recharge time. You can already recharge the ball by picking it up, decreasing the recharge time will just make the ball even more spammable.
Bonk! Atomic Punch: Who? Nobody ever said that Bonk needed a nerf- if anything, it's underused- if you're gonna nerf it like this, at least add an upside to counter the nerf.
Pretty Boy's Pocket Pistol: I like it. Makes it a good sidegrade.
Crit-a-Cola: I guess this is better than the original design, but I don't think it's a good enough nerf. Perhaps the Crit-a-Cola should make the scout slower?
Atomizer: I think this is heading in the right direction, but mini-crits while airborne? So, a market gardener for Scout? Not necessarily overpowered or broken, but just... weird. I guess the effed up melee hitreg is enough of a penalty to counter this...
Flying Guillotine: I think making it deal extra damage against Sandmanned opponents is still a fine mechanic, but perhaps minicrits instead of full crits? The Cleaver Combo only felt unfair because you were stunned, removing the stun is enough of a nerf.
B.A.S.E. Jumper: Quite the contrary, B.A.S.E. Jumper sollies are kinda easy to fight. Heavy, engineer, sniper, or another soldier with a good airshot aim and/or a Direct Hit will happily take down a parachuting soldier. Keep it as it is, it's perfectly fine.
Mantreads: Finally, these shoes might actually be worth wearing outside of Hightower. I like this change.
Darwin's Danger Shield: Uh... Sure? I mean, why the Sniper needs a weapon that makes him better in close-range encounters with Pyros is beyond me, but it's a helluva lot less broken than it was previously.
Razorback: The recharging shield is something that's been needed for a while, but the overheal penalty? I mean, I understand their reasoning, but if a Sniper wants to be pocketed, couldn't he just unequip the Razorback? The overheal penalty doesn't see effective at what it's trying to deliver.
Vita-Saw: So, it's basically the Ubersaw, but every hit gets you more uber in your next life... Yeah, while I agree the Vita-Saw is broken, I don't think making it a wannabe Ubersaw is the right direction to go in.
Crusader's Crossbow: Sure...? That's... all I really have to say...
All Miniguns: I didn't even know this was a thing. But I guess it makes sense.
Gloves of Running Urgently and Eviction Notice: Okay, who let the stoner write a blog post? The fact that the speed boost is only available while the weapons are drawn are a good enough reason to not pull these out during battle; if you don't have your minigun out, you're not shooting enemies, and therefore the enemies are shooting you because you're taking minicrits... It's not that the GRU (and the EN, to a lesser extent) are overpowered, it's that all the other Heavy melees don't give a valuable enough upside to those Heavies who wanna focus on our minigun.
Fists of Steel: Sure... I mean, this makes sense, although some kind of upside would be needed to counter this. Perhaps remove the holstering penalty?
Rescue Ranger: Yeah. I agree with this change.