What needs to be improved on the modular robot?

I have now had a working modular robot for a few days and I now know a few problems wioth the current design and had feedback from others. So this post is simply a list of potential improvements that could be implemented in later designs. Some parts of the robot require more work than others.

Edgebot potential improvements:

• Remove the need for a jumper for when the Photovore shield is not used, this could be replaced by two transistors and act as a switch when the Photovore shield is added
• Remove the two vias on the PCB

Photovore potential improvements:

• Find another source of LDRs, so that the sensitivity is altered so that it can be used in lighter conditions
• Convert the circuit to an Eagle schematic and produce a PCB

Motor controller potential improvements:

• Remove the voltage regulator, as it is not needed for the current boards and takes up a large amount of space on the PCB
• Add a second trim-pot, so that you can calibrate both wheels to ensure that it can go in a straight line
• Re-arrange various components
• Re-do all the tracks, in an attempt to get rid of vias
• Move the switch so that it is not obscured by the shields and add pin spacing so taht you can have an external switch
• Change the mounting hole layout, so you cannot attach it to the chassis in an incorrect orientation
• Add PCB to where it is currently not, at the sides of the board, as it is a paid-for area, which is currently not used

Improvements that would affect all the boards:

• Alter the stackable header format so that one of the 6 pin headers become an 8 pin header, this would cause less confusion when it comes to the orientation of the boards and it would also allow for more pins to transfer signals between boards
• Change the pad size to be larger, as this would make for easier soldering for people who are less capable

Chassis potential improvements:

• Make the chassis smaller, as there is currently a lot of wasted space, which is doing nothing apart from making the robot larger
• Make a battery compartment, so that the battery does not rattle around when it is moving, but make sure that it can come out when you want to change the batteries
• Change the motor mount design, so that the wheel can go on fully
• Add an integrated bumper at the front of the chassis, this would trigger the touch sensor when it drives into an object
• Alter the ball caster wheel design, so that the ping-pong ball is less loose
• Change the design so that wires are not wrapped around the chassis
• Rotate the LDR mounts to point slightly more outwards
• Alter the design so that the robot has a more level base