i'd like to see having a bit more control over weight balance basically not just legs up and down but a bit left and right as well prehaps a extended mode where the rounds only over after several hits (maybe 3-5) and if you ever do online multiplayer a basic level editor and some new ground types besides just normal and ice maybe rubber (super bouncy) and foam (hitting head doesn't count)
i noticed a few occasions where you could phase one block through another block letting you cheat on a few puzzles the trigger seems to be when the up/down and left/right arrows cause 2 blocks to grind together at a 90 degree angle when pressed at the same time and both blocks are moving
i wasn't exactly sure if the battle happened because of you or you just got caught in the middle its a great story about how anything can suffer for our ignorence even if it's only trying to help