Here are my personal letter grade reviews for levels submitted by authors A-C (technically NUM-C) corresponding to pages 1-6 on knyttlevels.com
Disclaimer: I don't consider myself an authority on what makes a "good" level. It's a lot easier for me to fill in a single letter on a spreadsheet than spend hours making these levels so if a particular grade seems unfair I am more than happy to give more in-depth thoughts on any particular level.
What each grade corresponds to: OUTDATED Obsolete versions of levels (see newer version for review)
N/A Tileset showcases, demos, etc. that can't be judged for gameplay
--- ---
F Unplayable or broken
D Severe issues (see criteria below) that makes completing the level unenjoyable, will not replay
C Average levels, no strong feelings one way or the other
B Great levels that are replayable, or great level concepts
A Must-play levels
Things that may negatively impact grade (-) : Broken levels / no ending
Random tile or enemy spam
Excessive "hallway screens" that pad-out level with no challenge / noteworthy visuals
Unnecessarily long walking period before receiving run powerup (unrelated to challenge)
Arbitrary hidden spikes / invisible death tiles
Wall clipping on screen transitions / void pits
Poor distinction between foreground / background tiles
Poor save point placement (e.g. save point > multiple hallway screens > challenge)
Surprise death by environment/enemy immediately on screen transition
[Outdated]Sheets link: https://docs.google.com/spreadsheets/d/1dHLxjO63eIP4owuM2rJK0F1k7CLFGbMIV9WbTV8H2o4/edit?usp=sharing
STATS: https://imgur.com/a/wlGZoM6
SORTED BY ALPHABETICAL: https://imgur.com/a/llts01m
SORTED BY GRADE: https://imgur.com/a/0WNviDNThe above links are out-of-date, see here for the latest version: https://nifflas.lp1.nl/index.php?topic=7484.0