Alright, here are a few pictures. I'll try to approach it as neutral as I can, and you guys tell me if anything looks more-obviously-wrong than I can see.
Some of the pictures are flipped, being right in one photo and left in the other, but hopefully you can make sense of it.
Let's play Find the Fret! (I already said where it was, but if you missed that in the OP, instead of going back and reading, look for where it's bending too much.)
Just started bending, with only some twist removed.
After tempering and adding in some reflex.
Last bends with the "long" string.
Low brace.
"Short" string pulled to I think 14".
This is a good opportunity for you to really fine tune your tillering.
It may well be that saving some to use as a teaching tool wouldn't be a bad idea. I've read many times that black locust, for instance, is a bowyer's best teacher.
In my (perhaps unfounded) opinion, these particular pieces are just bad. I'd wager more unforgiving than locust, but I don't know. It's just that on all three the tiller isn't that far off, again, in my estimation.
Plus, on top of that, many of the staves are somewhat sub-par, with twist etc. It'd be a lot of work with the heating and twisting and in some cases backing just for a lesson. Plus, if black locust is a teacher, there is black locust around -- I just need to find some that's not in places like public parks....
Check the mass on the bows that you allready completed and see what it is. We have a phrase around here we quote often but not often enough. " never bend the limb any further than what it takes to expose an area that needs work, this might mean two inches of bend. Try again!!
I really should get a scale and try tillering by mass. That said, I already follow the "no set tillering" method that you've outlined many times pretty carefully. It was one of the easiest ways to see good results as a beginner/novice. In this particular case I was able to pull to 16 without losing any weight, but when pulled to 18 I'd lose just a bit. So I was basically just working on weight reduction. It had only been pulled to 18" about 6 times.