Do you think APFT and Height & Weight failure fines would assist in self motivation?

Introducing "fines" would not be self motivation. That's negative reinforcement which is external; quite the opposite of self motivation. Also which we already have and it's called a chapter.

SFC (Join to see) I think that I know where you are coming from. You are asking essentially, is there a way to further motivate?

I think that the way to travel would be to offer an incentive for excellence? Does not have to be much-a day off, a 3 day pass, not having to attend field day one week.......but recognize that excellence.

I think that if you go over and above the already in-place issues that "marginal" troops are facing, it just beats them down further. That being said, if you are a SM and you are being beaten up for weight, for run time, for sit ups, for whatever PT related issue, you should not be sucking down whole pizzas, cleaning out the Golden Corral Buffet, wolfing down ice cream etc. If you are borderline-and want to stay-you should show through ACTIONS that you mean it. As your 1stSgt, I should have no problem going to the Command and saying "keep him, troop X is doing A, B and C, is dieting, is ......." Your actions should speak.

Additionally, and this is the opinion of ME, not the AF, the ANG, my Unit, ME: if a troop can blow out every aspect of the service fitness test-but is carrying a couple extra pounds, they need to be worked with, not just booted. I know of some fan-frigging-tastic troops that are just big dang guys. They can push the earth down, and run like gazelles, beating out 155 lb guys, but they are constantly at war with their waist, because their arms are the size of my legs. They can rip the doors from an up armored Hummer, and carry my tired, old, unconscious body and my crap 200 yards to safety. The little fella is going to mean well, but we also need to have some big guys-big guys that can do the job, not just slovenly, lazy, do-nothing guys. There is a world of difference.

SFC (Join to see) being in the reserves I am sure that the bigger issue would be will these Soldiers show up? If they know they will fail they will not show up to take the test. When they do realize whenever they show up that we will make them take on we will have a non-participant and then that is wayyyyy too much paperwork to do and try to process them out to really just try to improve numbers in APFT and ht/wt passing. There are standards and they should be enforced, but you have to realize that you still need "butts in seats" to fill our roster.