While I was offline due to Hurricane Ike, I did a few sketches of some designs for CAP 5. Some of these design draw from similar themes to other designs posted, but I think mine have their own flavor, and may merit further consideration.
I have intentionally tried to keep all my designs simplistic and "cartoony". On past CAP projects, I have been accused of making designs that "don't look like pokemon". So on this project, I'm really trying to keep the designs very straightforward, without too much intricate detail.
The first design is a "Planet Pokemon":
The goggles give it an astronaut feel, which makes it seem fast and special (vs physical). The "planet" concept can incorporate several moves. Not the least of which is Weather Ball. Since this is a planet, I think weather powers make a lot of sense. The little moons would be colored as gem-like orbs. These could be used for all sorts of special moves, not the least of which is Power Gem. Also, although I know it won't be used this way -- if a planet doesn't get Rapid Spin, it's a crime... same for Gravity...
My next design is a "Meteor Pokemon":
I was trying to make a design that looked like kinda like a rock spaceship. The clear canopy is there to give it that spaceship feel. The shape of the design is meant to look somewhat aerodynamic (therefore fast) but still look like a rock. I imagine this as a space-traveling pokemon whose natural habitat is meteor showers and asteroid fields. This pokemon could have an interesting backstory with Palkia and Dialga. Even though this isn't a physical pokemon, it would have to get Meteor Mash.
My last design is a "Pyramid Pokemon":
This came about after playing with various geometric shapes. Obviously derives heavily from the pyramid design on the back of the US dollar bill. I think this conveys rocks very easily, and the eye makes it look special-based. It doesn't look particularly fast, which hurts it quite a bit. I considered putting carvings into the side, maybe the braille patterns used in various caves ingame. Possibly the carvings could change like Spinda's spots or Unown's shape. I think pyramids are cool and for a pure Rock pokemon, I think a pyramid could work.
Depending on feedback on these I may make tweaks to one or more and possibly do a full ink and color, if it looks like it has a chance to make it to the final poll. Comments are welcome!
EDIT: These designs are in order of my personal favorites. Meaning, the Planet design is my favorite, and the Pyramid is my least favorite.