None of these have to do with haki or general combat feats other than the first one
Marco can hold back literally anyone in the verse with his fruit until he runs out of stamina, that’s why it’s broken. There goes point 2 and 3
Keeping 2 commanders at bay again with his broken fruit
We have yet to see him do anything impressive without his fruit, just being real
Kata can’t pull them off because he doesn’t have the Phoenix fruit lol
All of Marco’s best feats (only feats really) come from how broken his fruit is, I don’t know how you don’t see it
Haki isn't the only thing that constitutes "skill". Marco was nowhere near WB when Kizaru's light beams were almost reaching WB, but he came in just in time intercepted the attack, and stopped it. You need crazy speed and equally crazy reactions to move that fast. Marco doesn't have solid flames, they normally let the light pass through them, but he blocked Kizaru without letting a single beam reach Kizaru. Blocking light with flames is the mother of all skills.
Mastering DF tasks skills in the event that you're not aware. It's generally even harder to use a completely defense-centric fruit like Marco's for offense, which he does very efficiently. Granted Marco's fruit doesn't help a lot in stalling people, but you don't hold off top tiers and more than one YC-level character just by being able to regenerate. You'd get swatted around like a fly if you're not able to fight back.
Also, people need to stop their obsession with the term "advanced". There are enough people without advanced abilities that can fight on par with if not better than the so-called advanced ability users.