I have no experience with saucers, but it probably wouldn't be lower than 3:1, because that's the minimum allowed by NAR in its safety code.Is it still 3:1 minimum? Or is it different because there are no fins / angle of attack. Or at least it's quite different.
So, 3:1? Lower? Higher?
Yup, long burns are best, but you need enough thrust too.The problem with any saucer like rocket is not just the thrust to weight. It's the drag. You have to have enough thrust for weight and high drag. I've had some arc bad and others not. Sometimes it's tricky. The wind can be a factor with lower thrust as well. Higher wind makes it arc more. Higher wind needs higher thrust. I've flown up to a 54mm five sided saucer with a K motor. Went straight up in 10-15 mph winds. Saucers and their type have high drag and need more thrust than a normal rocket.