I think it is very hard to compare power levels pre-TS and post-TS, I'm a die hard OP fan, have been since 2003 but let's not pretend that OP is wholely consistent, it's nowhere as bad as in most other manga and the power levels are still prety tightly under control by Oda but there are some weird things here and there, like Croc pre-TS, and how absurdly OP even someone like Sabo looks even by MF standards, its almost a 2 decade long manga so this was bound to happen. And this is bout to continue I'll wager anything that the Yonko, the Admirals and someone like Mihawk will all pull stuff many times more impressive than MF. I do think a lot of this has to di with Luffy's power dcaling throughout the OP timeline, the stronget the SHs get the more intense the powers of all the side characters become, whether they are stronger than chars before them or not (Pica is one example, he looked like meh in DR but look at what he did, he basically changed tha landscape of the island, imagine what else he is capable of ... and he is nowhere near the top ppl in OP)
until Zoro beats a Yonko no.2 I will view Ace as the stronger one
#writingonmyphone