after a maximum of about 90 seconds after they cross the restraining line,if the attacking team is not trying to score then the refs call a stall and they must keep the ball in the box.
Great debate. The revised box proposed would come into effect after about 90 seconds according to your post. Well, where does this 90 second clock sit on the field? Isn't this the same expense as a shot clock in the first place?
The counter will be that the referees will keep that 90 second timing on the field as an approximate timing to get the game moving. Forget about the NCAA or youth match where about 110-120 seconds remain and the 90 second rule which is based on the referee's discretion never gets called. We will leave that side debate off the table for now.
If the shot is saved and travels out of the box, or the D deflects a ball and it travels out of the box, the O has another 90 seconds max to run a play or a new stall is called.
Doesn't this invite a new tactic where shots (which will require definition) go faithfully flying over the goal through the back ten yards to out of bounds - but the ball is returned to the offensive team for a new 90 seconds?
At the end of the day, this discussion starts with the words "... after a period of 90 seconds ...".