Goon Mission Guidelines
Use Trigger Zones to Signal Mission Start
Enemy groups will happily run around and burn all of their fuel, move towards their objectives, or timed objectives will tick down, which can cause dumb things to happen before goons even manage to take off. To fix this, place Trigger Zones around starting airports and hold off on activating mission essential units and timers until a player has left the trigger zone.
AI CAP Sucks
The default AI cap behavior is "find target, then chase to the ends of the earth" which can bait the AI out of position or into dangerous situations. Instead, use Waypoint Actions to tell the AI to Seach then Engage in Zone to actually get it to stay in the region you need it to patrol.
Prespawn Late Entering Assets
Make sure at least one of every unit intended to participate in the mission is spawned at the beginning somewhere. If the unit type is meant to show up late in the mission, place those units in a remote corner. This forces clients to load and cache models for the units at the start of the mission, instead of spiking lag mid-mission because everybody needed to load the asset.
Spread Out Activations
Lots of groups activating at once causes the game to chug. If you must activate lots of groups, do so far from players and teleport them to where they should "spawn" after their AI is started.
Use Trigger Zones to Reduce Processing
AIs, especially SAMs, do all kinds of complicated shit while their AI is active. Setting trigger zones such that the SAM is only active when a player is in the zone is a decent way to reduce resource usage.