Thanks for the feedback! Definitely hear you on the pins starting in the level, we initially wanted to have both pins and platforms available in a little "toolbox zone" or something that you initially drag from, but unfortunately didn't get to that and many other things, amongst which, as you note, was a cohesive character design. I think he's like a purple lumberjack styled after kingpin from spiderman, but beyond that I can't say. Maybe those things will come in a more developed version later :)
SPOILER: For level 4, place the small bit on the ledge to the right of the player, and the larger platform slightly off to the left of the target platform so it tilts over to the left. By the time the player knocks over the first platform, turns around, and comes back, you should be able to place a pin such that the larger platform rests flat and gives a path to the finish.