Hey Ranger X, I played your Sack on the Beach level. Don't really know how old it is so forgive me if I'm criticizing too much or saying things you already heared.
First of all: I like it. It has a consistent style and a polished feel. Liked the beach folks and their houses and love the day/night cycle (and how the people actually move at night).
The idea of having an 'adventure' type of level is a good one, but needs some work. Getting the wakeboard is nothing that really gives a sense of achievement or poses a challenge. I already got it before I even talked to the guy, accidently.
Maybe you should try to branch the open structure out a bit more. Now you only have left and right and don't really play with the verticality. Why not a huge ladder into the sky or a zeppelin? And an underground tunnel? Make the town your hub and make your side missions in four directions: up, down, left, right.
Also the stickering felt a bit tacked-on and boring. The idea of 'side missions' is a fun one, but do more with it. For example, make side missions that make the boss fight a bit easier as a reward. Or have some nice visual effect be the reward. Or win some hot islander... Just try to be a bit more creative and original than only giving some bubbles.
The platforming stuff felt really polished and well worked-out, although a bit by the books. The level clearly feels very polished and does not have a single frustrating or half-working part, but also feels quite unoriginal in the gameplay department.
Then the boss. He's nice! I like it that he has a clear attack pattern and his difficulty is very well balanced. The only thing is that you don't really have an indication of his health...
And one obvious 'bug' that you should really fix: after you beat the boss and you accidently fall down to that area again, you're stuck. You can't get up again. Make the save point move upwards or let the grab-thing respawn. It's quite easy to fall down as well.
I did actually really like the level, it feels incredibly polish and has a nice atmosphere. It feels very consistent as well and does not have one low point. I just think that you should be a bit 'crazier' in the gameplay and style. But kudos to you! Guys like you keep LBP alive and I like that a lot. Still have quite some of your levels to play and looking forward to that!