OP was still following a formula at that time. I would say it lasted up until Enies Lobby. After that the series became more nuanced - it wasn't just "good guys fight the bad guys" anymore, with a villain for each hero.
Look at Marineford or Impel Down. LOTS of fights, but nowhere near as choreographed.
Eh, it's still following the formula i'd say. Just that parts of the crew get skipped over in certain arcs, which was true going back to the very beginning (like Nami not getting a fight of her own until Alabasta).
The difference now is that more arcs are not conventional fight arcs, like Sabody, Impel Down, Punk Hazard and (for now) Totland.
Marineford was totally a conventional fight arc, just involving a different group of people, and that Luffy didn't really get a one-on-one (closest was his run-in with Garp). Otherwise you had stuff like Whitebeard v. Blackbeard, Ace v. Akainu, Marco v. Kizaru, Jozu v. Aokiji, Jinbei v. Moria, Hancock v. Smoker, Crocodile v. Doflamingo, Ivankov v. Kuma, and Vista v. Mihawk.
Not that all of those were very evenly matched, in one direction or another.