The timer board is a critical part of the game, especially the penalty clock. Whilst these scoreboards are expensive one thing we could do as a cheaper alternative is to have 2 smaller digital clocks over each sin bin (similar to swimming pool ones or something), with like 1 ft high letters (I've seen these before, just not sure where from). When a player goes in the timer starts counting down. When the timer hit's zero he can come out (obviously), although not as prominent as the big score board at least players get to see the box count, and would be cheaper than having one big computer controlled board. You could maybe have a central game timer controlled by a time keeper or the ultimate also.
If you were to have an event, you should publish the field schematic as far in advance as possible. X-Ball relies upon a lot of preparation and planning. The fluid show play seen at campaign is representative of team prep. approach X ball with a 7 man mindset, and you'll likely get prolonged points and a relatively dull game. Allow teams maximum preparation time and the chance to formulate simple game plans (firing lanes and primaries). I think the organisers would have to commit to either a 2 day event, or having the field up and available at least a full day before hand for teams to either utilise (practice) or plan (i.e. give them an allocated time sport to prepare field walk etc). Preparation and planning are what give you X Ball, not the field and certainly not the amount of paint.
One other thing, you'll need Air in either Pit area, so you either need a central air source (between the 2 pits), or two lots of fill rigs.
Paint consumption may well be higher, but should you talk to the right people, and present the right format / plan, you might find some support forth coming. It may come down to a restricted brand(s), but as a rule X Ball is an unforgiving format, and if your paints below a certain quality both you and the opposition will suffer. Present an option where maybe only 2 premium brands are available at a good price, you may get some backing. It's good business sense as they get to showcase top notch brands, and obviously shift a whiole stackload of paint in a single event.