I worked more this past season with the drivetrain side of things on 1293, so my story will focus on that. After Kickoff, we pretty much threw every single drivetrain concept out there: 2WD, 4WD, 6WD, treads, omni drive, you name it. From there, we started hashing out the pros and the cons of each. Our experiences in 2005 with Ockham's 2WD setup threw that out the window right fast. Omni drive was also dismissed rather early, due to the software kung-fu required for it in some key aspects of the game. (We had a new programmer this year.)
From there, we hashed out the pros and cons of each arrangement. Tracks offer more surface area, but if anything goes wrong with one track, you're driving in a circle for the next minute and a half. 6WD is heavier, but it turns better. 4WD adds some stability at the expense of turning. This pros-and-cons discussion went on for a while, and we kept coming back to 6WD as the setup that offered a good solution to each category we wanted. Would it be the best in a situation? Perhaps not, but we tended to agree that pretty-good across the board beat alternating between superior and miserable.
Most of our decisions tend to work out like that: lay out the options, throw out the ones that we knew could not happen (using six IFI wheels, for example, because of cost reasons), hash out what would work well (use two IFI wheels on the middle, then four Skyways on the corners), then go for it. The result,
JVN jokes aside, worked out pretty well for us.