Chip's Challenge 3 is apparently happening eventually. Here are some improvements from CC2 that I would like to see.
A sand tile. This would block monsters and blocks but allow Chip and Melinda (with hiking boots?) to cross. There is no tile with these properties in CC2 while even Chuck's Challenge has one. Using fake green walls as a block blocker is awkward.
A no-drop tile. An overlay tile that prevents boots from being dropped on it. Blank no signs and no signs with irrelevant tools technically do the job but they are unsightly and don't convey their intent as well as a dedicated tile would.
Native support for zero-directional blocks. This is the most commonly used "hacked" tile and is a logical extension of the other directional blocks.
Wiring on a separate layer. Wiring in CC2 is powerful, but still held back by their restriction to being placed on just floor and steel walls. The ideal solution is to combine the best of CC1's connection system and CC2's wiring system and allow wires to exist on a dedicated layer. Visibility while playing a level could be toggled by a key and they could appear as a transparent overlay. This would also fix the oddity of pink and black buttons not appearing when hide logic is on.
More consistent monster behavior. Bugs and rovers should not avoid canopies. Fireballs and ghosts with flippers should not avoid turtles. Rovers with fire boots should not avoid fire.
Support for bowling balls starting on clone machines. The ghost setup takes up an absurd amount of space for such a simple result.
Allow blocked green teleports to be skipped over.
Support for lowercase letters.
Give teeth monsters north-facing tile, and give blue teeth the same number of animation frames as red teeth.
Automatic recording while playing a level, like Tile World's. This should be easy to apply to normal play since it already exists in the editor.
Higher res graphics, 64x64? No 3D graphics like Puzzle Studio or Chuck's Challenge please
Extra green chip/bomb tiles.
More diverse sound effects. CC2 has fewer sound effects than the original Lynx game despite the wealth of new elements.
Important bug fixes:
Disallow hooks from attempting to pull monsters.
Disallow the player from being able to slap monsters.
If blocks can be pushed consecutively on floor, allow them to be pushed consecutively on force floors.
Trap logic fix, including multiple trap button problems and the issues with wired traps
Consistent snatching and hook block slapping behavior (i.e. not monster order related)
Flame jet max distance fix
The two disappearing Chip glitches and the Waterbirth glitch
Thin wall on closed side of railroad should not have any effect except when the RR sign is equipped
Allow player to step off force floor if they start the level on them
Allow key inventory to exceed 255.
Want-to-have fun stuff:
Allow blocks to be pushed at 2x speed when Chip has speed boots.
Make blocks have no effect on recessed walls. This would revert their behavior back to CC1. Ice blocks and directional blocks would still be able to be pushed on them, and turtles could still retain the CC2 "flicking" behavior.
More thin tiles: walls are the only tiles to have thin versions of them even though other tiles could be adapted to this concept. Puzzle Studio has thin toggle walls. Thin gravel, thin force floors, thin recessed walls, etc. have potential.
Lasers: Puzzle Studio and Escape have these. A beam it shot in one (or more) directions until stopped by a wall and other elements like blocks and perhaps monsters. Chip dies when hit by the beam. Maybe a beam receiver that converts the beam to an electrical current.
Reflectors: Chuck's Challenge has these, though they apply to the spitter enemy. Pushable block that reflects bowling balls and lasers 90 degrees. Could be rotated with train tracks.
Logic gate enhancements: Add NOR and XNOR gate for completeness. Add diodes which allow current in only one direction, the ability to specify a delay in frames from 1-10, which will make synchronizing circuits easier and remove the need for chained OR gates (Circuit City contains an example of long OR gate chains)
"Frictionless" blocks (don't have a better name): Copy of the yellow blocks from Escape. These are blocks, once pushed in some direction, that continue on a straight path until they hit an obstacle. Think of tanks but pushable in any direction by Chip.
Score gate: Exists in Challengo, essentially a socket that the player can open if they have enough points but will deduct from their score.