Battles are part of One Piece, they are inevitable to reach the goals of the SHs, never denied that but a battle manga is a piece that builds his premise on the fighting as the goal and as main focus which does not apply to OP. I have seen the term falsely used a lot of times. Everybody is free to take what they want from the story, in this case the battles for you i guess, but calling it a battle manga reduces the content only to that which does not do justice to One Piece.
I understand what you're saying now but "Battle" isn't actually a genre. Genre's are School Life, Sports, Action, Adventure, Romance, Shounen, Shoujo, Mystery etc.
One Piece, Naruto, Bleach are all battle mangas. But Battle is just a term to define the concept in which the vast majority of challenges are overcome.
In One Piece, it is a fact that the challenges towards the main cast are most commonly overcome through combat.
Therefore it is a battle manga.
Battle isn't the main goal of any manga. Luffy wants to find One Piece, Naruto wants to be Hokage and rescue a friend, Natsu completes missions in the hope to re-unite with Igneel etc.
So it technically still correct to call One Piece a battle manga but you're right its much more than just Battles.
We already have thoughts that whoever Akainu sent after Luffy and Law is an admiral, though I hope that's not the case, otherwise Luffy might fight them instead of Doflamingo. Besides, it seems too soon for Luffy to go up against an admiral (and win).
I agree here. I don't think its time for Luffy to simply take out an Admiral. If he does it would need to be an insane battle and not a Luffy VS Blueno situation.
Then again it could be a situation where the fight doesn't necessarily end. Something thats common in One Piece.