I´ve played some of the Group 3 entries, here are my impressions:
Kirbyguy (B725-0000-0058-CA7B): Felt too difficult for a 1-1. Enemy placement made them difficult to engage, specially the Winged Koopas coming from above. There are many bottomless pits and the level felt too short and without guidance. There were some nice secrets.
Dad (04F7-0000-004D-D67C): Very good level, There are bottomless pits, but coins are used masterfully to guide the player around all the level. Enemy placement is perfect, always giving the advantage to the player and announcing them with enough time to come up with a plan on how to engage them.The whole level´s layout is thought to guide the player in a non-intrusive way. Really good work.
MaxwellGT2000 (5E82-0000-001E-F62F): This level didn´t feel like a 1-1. Bottomless pits everywhere, lots of enemies thrown at the player at once from tricky positions (the level even starts right next to a pipe spawning Koopas above the ground before you can get to the first powerup), lots of different enemy types, requires running, running jumps and even a running jump with a spring over a wide bottomless pit...There is no continuity or evolution in enemies, mechanics or challenges. The Copter powerup had no sense, you just get it a few meters before the goal so there´s no chance to really use it.
Lady Siara (6D34-0000-003F-420E): Several Hammer Bros are spread over the level, which makes it too difficult for a 1-1. Running is required in certain parts and I saw some things that made no sense, like a Spiny trapped between some blocks and only accesible from above (which would kill the player), but in a place where it was easy to see, so I really couldn´t understand the purpose of it, it felt really out of place.
Sixfortyfive (EC81-0000-0059-CE01): Very intelligent level layout from start to finish. This level does two things that I felt were specially remarkable: the first one is that invisible blocks are used in a perfect way to teach the player about secrets and rewards. The other was putting a Koopa into a Question Block. This is usually a big no, but it´s used in a safe setup and to guide the player towards the completion of a small puzzle and teach him a few things about Koopa shells and block interactions. Genius. The enemy placement through all the level is perfect as well. Awesome level.
I´ll review the rest in the following days.