I will go a different direction and actually list some of my complaints about the writing.
1) Oda didn't do the best job juggling all the different characters. Guys like Kizaru basically did nothing the entire war, which seems really unrealistic in the big picture.
2) Haki was very rare on the battlefield. I know, it just got introduced back then, but it just didn't age well in hindsight. Nowadays even battles between mid-tiers are pure haki-fests.
3) Almost no casualties outside of Ace and WB. I mean come on ... this was a full-blown war and Oda didn't have the balls to kill off any other minor characters. Just a few more would've been enough to show the drama and brutality of this war. As it stands right now, Ace and WB being the only deaths is a bit cringeworthy if you look at it realistically.
I agree with you, that Marineford is vastly overhyped btw.
I rate several other OP arcs way higher (Jaya/Skypiea, Water7/Enies Lobby, Sabaody, Impel Down).