I'm trying to follow the event daily missions, which also reward rosepetals or whatever they are. So 10 stamina map once, 20 stamina map once (it got 2 of the required mobs), 40 stamina map twice (also has 2 mobs), 80 stamina map 3 times. Total is 350 stamina, so the rest is for extra 80 stamina maps.
As for team setup: the past couple of events, I could use my regular unit in its default setup at standard placements for the 80-stamina events for full clearings. Teams are ordered from slowest on squad 1 to fastest on squad 4: 466 speed, 503 speed, 611 speed, 897 speed. Most maps seem setup in a way that the helper squad hardly encounter any pests, so I prefer teams with Mei and/or Cattleya, since their 50% light gauge fill is one of the few ways a team can actually help other teams.