Gotta give it to Lucci, dude broke through a solid CoA barrier. With his speed and skills and that kinda penetration power he's a very dangerous foe.
But man, Luffy lowkey got insane feats this chapter. That's an awakened Zoan, that he nearly knocked out in that one attack and that attack does not even have CoC in it. And he's speedblitzing into that pipe within a millisecond basically, while simultanously switching from ggn Giant into his normal size. And his ggn Giant is huge, well above 20m I'd say. Dayum..
Still think Nika's goofy trope is what balances it in a thematical sense, so that luffy does not feel too op for what's left in the series. The shown named attacks are still just "imagination" boosted base attacks from earlier times. If gigantification and that G4 mechanism comes into play this will be put onto even further levels again. Really want to see how other top tiers will handle all that.
But I really don't get the idea behind the aging or elasticity loss-effect post G5. A potential stamina limit does not make much sense, when he just can go back into G5 by manipulating his heartbeat anyway. And long term consequences are imo far too serious for stuff that's basically just normal DF business. I honestly don't get where Oda wants to go with that.