You would want to yolo until 14* then SF to 15* then yolo to 17* if the equipment is cheap to replace. This would include gollux gear as clean gollux gear is still too cheap to consider using SF. The cost of yoloing to 15* instead of 14* far exceeds the SF boxes in terms of meso, higher boom probability and time to click. There's no point of using SF boxes at 15* to 16* just because the rate of getting to 16* without booming is over 90%, and the amount of SF boxes needed to get to 16* would make it cost too much money for anything that isn't arcane.
In fact the best possible way is to possibly just SF straight from 13* due to the sheer amount of time clicking just to get to 14* which in that time frame you can easily run vj mp 20 times.
for arcane you have no choice but to SF all the way due to how expensive it is.