It's hard to say, One Piece does take getting some use to I admit that fully.
What happened to me an One Piece was that my sister prompted me to read it a very long time ago, I picked it up, started to read and... I didn't get it.
I was put off by the art, it was to weird to me, I just... didn't get it, so I put it on a shelf, for YEARS.
Then one day, I got a crick in my back, I couldn't move from my bed, at all, and for some reason... I have no idea why, years after having given up on the series I thought. "I'm gonna give One Piece a go again." and started to watch snippets of the anime.
By the end of that back-pain exsperience, I had turned from "Meh." in regards to One Piece I had known of for years into. "OH MY GOD THIS IS THE GREATEST THING EVAAAR HOW COULDN'T I HAVE KNOWN?!"
Some-thing like that at least.
I do think some of it has to do is that I gave myself the time to be really indulged in the story, I will say One Piece does start off kind of slow, it's amusing in the beginning and becomes better in retro-spect as these all things pops up again and are used in new ways, though yeah, in the beginning in the set-up phase, it does look like a regular manga.
And we have to go pretty far before suddenly it turns around and you realise it's any-thing but, the Water Seven arch is just the manga reaching a whole new level of. "Omg!"
But that's pretty darn far into the book.
The Orange island arch is pretty emotionally involving and the Drum island arch where they meet chopper is the first time I had to sniff a genuine tear over this thing.
One Piece is a very different unique thing, there is little like it and therefor it does take getting some used to. Both in regards to art, humour and utter randomness (On the surface.)
It's okay if you never get used to it, with some-thing as unique as this, it's a lot to ask for that every-body will just love it.
But I hope you can have some fun with it and just laugh and go with it. It's a very funny manga and was so from the beginning, and it only gets even funnier as it goes on.