I've submitted my ballot for group 1 of the contest, some interesting levels and takes on the 1-1 theme so far, glad to see some creativity. I won't share votes, but I will give some comments.
BowieZ - A creative style, while staying true to 1-1 difficulty and flow, and remianing fun to play. The ending feels a bit janky but nothing bad really.
PSqueak - Too long for a 1-1 I think. One of the underground rooms threw me off a bit, but solid overall.
NetMapel - Goomba in a block is a bit trolly for a 1-1, good short length.
Orgen - Good concept for a tutorial but still too hard and too much instant death potential for a 1-1. Why does the last "big" secret stick me all the way back at the beginning?
jamesmccloud - I don't like the idea of an autoscroll in 1-1, and ended up finding the end of it first, had to ditch Yoshi to find the entrance, which feels bad. Overworld is good though.
VandalD - I like the idea of using the moles as the 1-1 enemy, and the stage is well thought out.
Anteo - This could work as the 1-1 for a game with a spring gimmick, but the level was kind of sparse otherwise.
Jocchan - Without a timer on the megamushroom, having it for the whole stage kind of messes up the flow, plus it blows up all the other ? blocks. Feels very 1-1 though.
Jucksalbe - The first half is good, the second half gets too hard. One of the hidden blocks in the mushroom platforms Kaizo'd me.
Yuterald - I love the level concept but I would not consider it 1-1 style at all, too many tricky sections, and the amount of death X's I saw seems to agree.
Junahu - Good example of a 1-1 level, but the first warp pipe brings me past the first Yoshi egg, seems like a bit of an anti-reward.
TheSlySoul - Does pretty much exactly what it claims to, but is a little too short, needed a little more space to develop.
BGBW - Good 1-1 level, I especially liked the spinning block blocking the pipe, not something I've seen before as a simple teaching concept.
Kriken - Kuribo's Shoe doesn't feel like a 1-1 mechanic, add munchers and saws (and a "ditch the shoe" jump) and it really doesn't feel like one. I do like the shoe though so I can't really hate.
Nohar - Feels like classic 1-1. Really could have used some different colored blocks, but I think you know that by now.
DryvBy - A 1-1 level by definition, but entirely derivative. Evokes a bit of nostalgia but needs a bit more to not just be a rehash.
ramparter - This is a level more out of SMB world 7 than world 1, too difficult and complex for the goal here.
I gave a star to all of the levels. Despite any criticism I thought they were all well done, but in this case I was looking with an eye to the "1-1" style and I tried to direct my criticism that way. An odd note, people really like the "kick a koopa shell for a 1up" mechanic for 1-1 levels (I did this in my level as well), but unless one of the NSMB games does it, as far as I know, the earliest level that actually has a section like that is 1-2 of SMW, not 1-1. I guess it's just too satisfying not to have.