What I carry depends on what I'm riding. I base the repair kit on what I've needed in the past.

Road: A 4mm, a 5mm, tube, tiny pump, lever and some €s. (I've never broken a chain road biking)
Mtn: 2 tubes, wide barrel mini pump, Topeak multitool with breaker, levers, spoke tool, and allens.
City: Zilch. Ditch the bike and return later, sneak it onto the tram, or ride the rim.