Yeah, it looks like Bracy and Kilty could push each other on towards that sub-10 time. Bracy is 4 years younger, but they are both at the same pace now. But Bracy might have the potential to be faster in the end - who knows. It's just another projection of course.
Indeed, Lemaitre is more 100/200 with his height, and Collio a short sprinter. Kilty is probably in the middle, but was concentrating on 200m up until last year, which could give him good speed endurance. Combining both sets him up well for 100m.
The weights/plyos for acceleration sounds spot on for me. I was always a slow starter and would come back at people with velocity/turnover and speed endurance from 60m onwards. If only I was taller than 1.75m (and started lifting weights/combining with plyos).
As you say with Kiryu, it's all in the results and not what-ifs. Light plyos got me from 25.5 to 24.0 in the 200m at 15/16, but then again I'm likely a Darrel Brown type, peaking before 20. Guys like Kilty and Dasaolu definitely are not.