Looks kinda interesting. Gives me hope that maybe OP doesn't suck so much once I get a little further. I've watched 53 episodes, I was able to do that because someone told me it'll get a helluva lot better, and because it does generally improve with each new arc. Occasionally it also has some brilliant scenes, though unfortunately always out of battle, the battles are so goddamn horrible I've never seen anything like it, not even in Yu Yu Hakusho. Except for one, the Zoro vs. Hawk Eye battle, that was pretty decent. It was hilariously anti-climatic to watch a brilliant build-up in that Nami-centered arc, only to have it conclude with a series of dragged out battles that effectively embody everything that's bad about shounen battles. When I continue watching some day, I'll probably skip most of the battles, unless and until they get decent.
It gets way better when you get further into it... the first half (or til the Water Seven arch - i don't remember the exact episode number), the arch with all those "Animal" fruiteaters, you've watched in the AMV, untill that arch, it seems pretty unserious, afterwards it gets more and more serious, it still has those serious moments, (the fight with arlong in the nami arch is an example, or overall the way Luffy wants to help Nami and the village)
Many things happens afterwards, which you also got a little taste of in the AMV:
Fights against several of the 7 Warlords
More people joins the strawhats (8 people so far @ ep 509).
Huge bounties on the strawhat (Especially Zoro and Luffy).
A War against the Marine, in Marineford, their base, where Luffy + alot of other pirates (The whitebeard pirates + allies), fights against the 3 Admirals, nearly all of the warlords and many thousand marines.
Luffy breaks into the worlds most secure prison, impel down, to save his brother.
my favorite fight from OP is: Ace VS. Blackbeard, awesome one, you'll be able to find many videos on youtube with it.
and yeah, especially in the start, there are some boring battles (ehmmm the usopp arch)
it gets better, but there are some very long fights later on too (especially Water 7 Fights)