Hey, to me, your background looks really solid! Maybe it is all about the programs you applied to? Some programs might not just have enough funding for international students even if your background is super strong and competitive. For example, I have heard that NIH funded labs are not really allowed to take internationals and cannot provide support to them. Anyway, I wish you good luck with your applications and hope you get the invite soon! It might also help if you contact the admissions of the schools you applied to to request some feedback. They might not be able to get back to you until after they finish the current cycle but it might be helpful.