Yeah I support you on this one.
But the problem with the Red Roc scene is, that there is no barrier haki release happening in that panel.
The thing is, the haki around his fist has to be released in order to create that powerful haki blast, that we call "barrier haki". Simply letting your haki flow onto your fist won't do the job.
Here he let a big amount of haki flow onto his hands, but failed to perform the actual barrier haki move, which resulted in him getting clapped by O'lin, cause no haki release was there to stop her slap.
Addtionally there is simply no visual in that panel that portrays that kinda haki release/blast.
The one that looks like it is actually just Oda's way of drawing an impact.
Circled in red.
You see the same on something like that..
There are a dozen of other examples.
Barrier haki looks like this
It looks completely different.
And like I said: Without the haki release you've got no impact.
Addtionally Luffy's fist actually made PHYSICAL CONTACT with Kaido's face. It's what punches him into the ground, not some non existing barrier haki release.
There is simply no argument there for it being advCoA lvl1.
Like I showed above, his fist actually makes physical contact with Kaido's face though. There is not haki release happening.
And the tree scene is misguiding. Yeah in an isolated scene like that, the space gap between the fist and the haki blast gets portrayed clearly and we also can see the haki blast happening, because the tree or the collars actually explode. But all that is not happening in an actual combat situation.
The opponent's head won't explode and because of the fact, that the haki blast is put into the opponent's body, it won't make physical contact with the exterior of the opponent's body and therefore the fist still makes physical contact. Something that for example can't happening if barrier haki is used, because then the barrier haki makes conact with the exterior.
That's also why Luffy's base advCoA lvl2 moves won't be as strong as his advCoA lvl2 gear3 or gear4 moves. The physical attack still makes contact and therefore counts.
We actually have seen it before
You see, Sabo's dragon claw makes contact with Burgess armour before his haki blast destroys it from within.
Same happened with the exploding collars.
Now the question is: What's up with that fire? I mean is it actually real fire, as it is during "Red Hawk" or is it Haki, that's just drawn as fire, solely for matching the theme?
And that's where I also have my problems with. I mean a smaller version of G3 with fire normally shouldn't be that powerful and especially not powerful enough to hurt Kaido. And the Red hawk mechanism also is missing. Furhermore he just came from a haki training session. All of it just doesn't add up. But the visuals are suspicious.
I'd argue it's an advanced CoA lvl2 move, whereas the surrounding haki gets drawn as fire,. It's probably there to match that certain theme as a 2.0 call back to Ace. Similiar to how during Thor Elephant gun, where no actual lightning is involved aswell.
And because of advCoA lvl2 it is also able to damage Kaido this much.