These are my ideas for new blocks to be added to the default Classicube block list.
Light - A block that will emit the lamplight color with a stength of 15
Door - A block that the player can walk through. (If its possible, make it so the door can be toggled walk through/non-walk through)
Concrete stair - Block that players that can walk up (NOT climb up)
Arrow block(s) - Blocks that have arrows on them that point in different directions.
Cushion - A block the size of a slab with a cusion texture (if its possible, make it so the block toggles your model between sit and humanoid when clicking)
Slime - Block that slows the player but increases jump height while in contact with the block.
These are my ideas for new blocks to be added to the default Classicube block list.