For me, it's an organizer -- the more stuff I collect, the more I need to figure out where the hell it all is. Related to that would be an organizer that would protect the needles on ball gauges and pumps, as I seem to go through those things like some people change their underwear.
Now, the biggest problem is that you don't always realize what's missing until someone else tells you otherwise.
As things stand now, I carry the following in the kitbag:
- End pocket: Boots
- Main pocket: Kits, flags (in their own separate case)
- Side pocket (the one that needs organization): Whistles (2 on wrist-lanyard, 1 loose), two card books, several pencils/pens, index/recipe cards (for match cards), spare notepad, ball gauge, pump, competition badges, referee badges, LotG copy, sunscreen (seasonal), bug repellent (seasonal), talcum powder, tapes (white tensor, black electrical, clear medical).