Hey, last year's worlds was my first, this will be my second.
I didn't compete last year and won't compete this year - So I have no advice on that, sorry. Not competing wasn't a problem. On the contrary, the reason I'm not competing is because I don't plan or aim to be the world's best, I aim to have fun, and competition spoils my fun.
Regarding the fitting in thing
I didn't play as much as I could. During the first few days when I didn't know anybody, most circles seemed homogeneous either in level or in country of origin, and being like the 10th worst player there and the only one from my country, I didn't feel very comfortable joining most circles. Also, rooming with net players didn't do allot of good for fitting in shred circles, even though they were awesome people.
By the third day, though, I found enough people to play with, either around my level or that just didn't care about level (not enough of the latter, imo). Unfortunately the day after I got sick when serious rain caught me while I was touring Prague
Outside the shred court, level didn't matter as much. There it was down to who's just friendly and who isn't, and there were lots of friendly people. I was a little star struck some times which made for a few awkward moments but overall there are allot of people I am looking forward to seeing again.
Advice: Room with shredders if possible. Go to the parties. Join circles. Talk to people

If you see yourself competing in the future, DEFINITELY compete. The experience will be good for you.
See you there!