That's a bit far lol.
Lucci got dominated by G5, while Kizaru went kinda even with G5 until the finale where he got downed with that punch.
Maybe, but it's all headcanon and interpretations really.
At this point, I've given up trying to figure out what's no haki, advanced armament or advanced conqueror's in Egghead arc. It's upto guesses at this point, since Loda is very inconsistent when it comes to drawing haki. To the point we have to rely on headcanon to at least some degree, cause nothing is explained for shit.
As far as Loda is concerned, Luffy may very well be using advanced conqueror's in both fights, but just wasn't drawn. We don't know
We can at least assume Luffy was using advanced armament against Lucci, since well they had that clash with a lot of lightning showing up.
The only reason I don't presume Luffy used advanced conqueror's there is that I don't believe Lucci can clash equally with G5 Luffy using advanced conqueror's (i.e headcanon, a lot of headcanon is needed here cause Loda is shit with haki)
With Kizaru, probably the last attack was advanced conqueror's. Could be advanced armament as well, who knows?
I will just assume advanced conqueror's I guess, because it had thicker lightning, but also mainly because I don't think Kizaru would be down by one hit without advanced conqueror's haki.
I've always believe Luffy was mid top-tier. Amongst the Yonkos, I had him above Big Mom and Marineford WB, but below other Yonkos. And <= Oden, if that counts for anything.
But yeah, prior to this, I always had the OG admirals above current Luffy, while new admirals below him.
At this point, I guess only maybe Akainu is clearly above Luffy
Akainu > current Luffy ~ Kizaru ~ Aokiji > Fuji ~ GB
And quite honestly, it is arguable that someone like Kaido would not even need extreme diff to take down Kizaru, high diff might be enough. Since well, Kaido can fight at the level of G5 Luffy without the time limit (once Kaido got used to G5's wack combat, he was fighting evenly or maybe even started getting the better of him in CQC).