A game that has levels like this for sure will not get voted as best by me for being favorite, complicated nor design. No matter if those levels are actually really difficult to beat or have some really good puzzles in it I am even not sure if I even bother to focus on those if I can't beat those quick because considering how lazy design those have it is also not sure if those have been focused enough by the author to be beatable.
I write this because there are a lot of games looking a bit or more like this at Explore by random unknown users. PB is not a very difficult application I believe and I am sure even beginner should be able to make something better.
I also agree on it is sometimes exciting to just touch PB and check things out, making your first level very quickly etc. rather than focusing some real thing but I would not suggest pushing any experiments to an Explore section.