A few of the main things that I think will be kept for all FIRST games are the elements of safety, mobility and “cheapness”.
Safety: Making sure everybody is safe (or else they might have some legal issues). I think the reason they choose larger objects is because it is harder for them to fly off the field and hit somebody. If you have people throwing frisbees and tennis balls, it gets a little harder.
Mobility: Not sure if this is the right word I want, but it will have to do. FIRST is growing to like 29 regionals or something similar, and they need to make sure they can take all of the materials needed for the game easily. You can’t guarantee heights of ceilings and whatnot, and constructing one isn’t very feasible.
Cheapness: Keeping things cheap. I remember talking to one of the Regional Directors last year (after 2003 game) and they were really upset at that game (for many reasons obviously) partly because the bins would break constantly. Not very many bins lasted more then a few matches. This year was slightly different, but the 2x ball bursting was another cost hitter. I believe FIRST will go for something that will not take a hit on the budget.
But then again who knows…
Chris