Black Mesa changed a lot since the first mod was released and they heavily improved several aspects. There were always a lot of nitpicks I had, but even most of those were fixed at some point, some always remained and I never was sure if the developers actually think there is nothing wrong with these nitpicks, because they can't be so hard to fix (but I'm just speculating).

PLEASE don't get me wrong. These are NITPICKS. The final issues I PERSONALLY have with Black Mesa which prevents me from LOVING the game as much as I love the original. I would still recommend Black Mesa to anyone.

This is the most odd one. Since the animations stayed the same since the mod release, I can't but think that the developers actually think these are fine. The crowbar hitting animations look goofy and the sound effects are bad as well. I feel like they wanted to keep the super fast attack speed from the original, but since when are they trying so hard to stay true to the original?

There are plenty of places where they didn't stray true to the original (often with a good reason), sometimes deviated extremely (Xen obviously), but also with weapon balance, for example the ammo economy of the magnum, so staying true to the original can't be the reason. Maybe they just never got to it, but that's why I waited for the definitive edition to make this post, I thought this will finally be the moment they will fix this.

I know there are mods to fix this, but the crowbar is such an integral part of the game, and just simply iconic (they even bloody call themselves "Crowbar Collective"), and these animations in my humblest of opinions quite frankly are really bad, that I wish they officially improved them. I know many people whose first experience with Half-Life was Black Mesa, and they surely don't dabble with mods (they also don't care nearly as much as I do).

Gibs are great. I love gibs. The original also has gibs. Black Mesa's gibs are really disappointing though, for multiple reasons:

• The gibs are really goofy, and no, the original wasn't like that (and again, since when are they trying to stay true to the original anyway?). In the original humans didn't drop brains and eyeballs. For me it ruins the atmosphere and is just "cringe" tbh (I can't think of a better word, sorry).
  
• Creatures gib way too easily, far easier than in the original even! In the original soldiers didn't gib after a double shotgun blast or getting shot by the mounted gun (not 100% sure). The gore and violence in this regard is just waaay too exxagerated, even Mortal Kombat would be ashamed.
  
• The physics of gibs are the worst part of them. When a grenade explodes next to a human, the grenade obliterates him, launches his body parts over the entire room with insane speeds. Also really distracting are the sound effects when the body parts start bouncing off of the enviroment.

This one is more work to change and way more subjective. It's also not that big of a deal (all of these are nitpicks remember), but I feel like the zombie sound effects, especially the screaming sounds, are really cheap, especially compared to Half-Life 2 and Half-Life: Alyx (I'm not expecting them to compete with those, but still).

• Grenade & Rocket explosions sound bad.
  
• The weird particle effects trail when you throw a grenade are a super weird attempt at incorporating the red light trail from the Half-Life 2 grenade, which I asssume should make grenades more visible to players without a UI indicator. In this case it just looks much more stupid than it's worth it (please excuse the use of the word "stupid", as a non-native speaker I could'nt think of a better word!).
  
• Enemies touching barnacles and instantly becoming ragdolls and weirdly flailing around. This was always a nitpick of mine even for Half-Life 2, and even Half-Life: Alyx has this. Except Black Mesa is WAY more extreme and goofy with its ragdolls in these scenarios.
  
• Killing a headcrab with the crowbar doesn't feel nearly as satisfying as it should. In Half-Life 2 there is a really punchy sound effect when you hit the headcrab, but in Black Mesa it's just a very quiet sound.