You had 10 missile units, though. That makes a HUGE difference. No, they can't handle that. My typical in-campaign Venetian stack has 4 pavise crossbow militia, 6-8 venetian heavy infantry, 2 mounted sergeants for chasing down routers, and a load of generals for heavy cavalry. I'm not using any governors to avoid bad traits, so they all wind up in the armies. I've had as many as 7 bodyguard units in one army. In some armies deaths have whittled them down, so I replace the generals with feudal knights or Hospitallers. I prefer the St. John knights, but I've only got one castle where I can build them, so only armies near there have them.