Adding a bit of salt to alcohol fuel will give a yellow sodium flame without affect the cooking properties, and make it visible in daylight.

And as for cooking for multiple people, carry multiple stoves--or have them carry a few 10 gram stoves and a pot themselves, the lazy bums!

When on a big group van-supported tour, we used a massive cast-iron 2-burner propane setup hooked up to a one-gallon tank, that weighed about 10 kg altogether. That beats anything for cooking for 23 people. You can cook a heck of a lot of French toast in a hurry on something like that.