I suppose it depends on what the point of the routine is. Are you trying to score best or be progressive?
At Level 7, there are only two tumbling passes required. If a gymnast is doing a third pass at all (most do, I know), that third pass better not take any deductions becuase you get nothing for doing it. My dd is not a L7 but her gym only has two tumbling passes for L7 and the girls rarely score below a 9.5 on floor and there are twelve of them in that level.
Of course, what I say above is not progressive. Any time you are getting used to the stamina of three passes or competing more difficulty tumbling, the better. As there are no composition deductions at Level 7, it generally is pointless otherwise to compete a full unless 1) you do 3 passes at your gym so you must do something and 2) the full is a better quality pass than a tuck for the particular gymnast. Most gymnasts will take deductions on a full for piking it down or for initiating the twist early. It is NOT an easy pass to go clean on unlike a layout.
What order you do the passes should again look to quality. If the full is better at the beginning, do it at the beginning. There IS a reason to do it at the end in Level 8 and up. At Level 8, it can help with composition and at Level 9, it would be a B dismount which is minimally required.
Nearly everything I say ONLY applies to Level 7. Once you hit L8 and up, composition comes into play and the criteria shifts - especially at states/regionals/westerns/easterns/Jo nationals.
