But mostly we're ending up in a world where a human and a grizzly bear are totally the same, it's just that they have different proficiencies. And that is absolutely ridiculous. A level 1 grizzly will pwn a level 20 human in hand to hand combat. It won't even be tired afterwards. Similarly, a level 20 goldfish monk can kung fu punch a level 1 great white shark peasant all day and the great white probably wouldn't notice.
Now, I know we went past this, but I wanted to make some clarification. 5e doesn't work like this. It's something I tried to explain a few days ago, without success, but statblocks and PC follows completely different rules. A monster doesn't have levels, doesn't have level adjustments, nor racial bonuses, nor anything else. Statblocks lives in a vacuum.
I'm going to link to 5e.tools, which I'm not sure if it's legal or not, to explain myself better. Sorry.
A black bear is a black bear, there is not a lv1 or lv10 black bear. A
black bear is arguably weaker than a lv1 pc, except that for his hit points. Hit points that are defined by his size, not his "level" nor his CR (1/2) in this case, exactly in the same way an
Abjurer Wizard have a d8 hit die instead of a d6 as the pc wizards have, and a
Thayan Warrior have again a d8 hit die instead of a d10. Because statblocks don't follow the same rules as PCs.
I'm going further saying that since a black bear is weaker than a lv1 PC, I'd say that a black bear cub (the closest thing to lv1 bear I can think) would be ragdolled around by a
Commoner, who have the same stats of a
Drow Commoner, who again are the same of an
Orc Commoner (Full orc, not even half). Much of racial bonuses.
I understand that you want a mechanically defined world, I really do, but 5e doesn't even remotely works in the way you want. 5e is a different game. A game that sure puts in front "fun", it puts in front "ease of play", but most importantly it puts in front the narration. What does it mean? It means that at the end of the day anything that makes sense in the story, not in the world but the story, is fair play.
What I don't understand is why you want to change a system that, I'm sorry about this but, I believe you don't know even remotely, just to make it like other systems that already exists. Everything you want is already in 3.x, a system that I despise and that I can talk shit about for days, but it's there. Why do you want to turn this amazing narrative system that is 5e into that thing that was 3.x?
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About the immersion that someone brought in, just two days ago
I completed dming Beyond the witchlight to my group of three players, and I can assure you they were moved, estatic and sad about the end of a campaign that gave them so many emotions. They felt everything about that mysterious world that is the feywild, they understood how feys behave in a completely different manner than human, and all of this using tasha's stats and without all that bloat of "logical worldbuilding".
