Awesome work Cosmo =D
But don't decide which Gyms they are. You say that Mum is 8th, when I was thinking more of 4th.
Also, an idea. Unlike the Nintendo games, all of our Gym Leaders will have a story behind them. They may tell you that story, you may hear it from someone else, or you may have to piece it together, but it is always there.
Easy example of this would be your mother. She left you when you were a kid, and you didn't know she had become a Gym Leader until just before you face her.
Finally, some of constructive criticism:
Blossom's hand is too straight, it needs to be slightly rounder.
A piece of Blossom's hair has the end cut off (right side, on a spike)
Blossom's hair again, bottom left, needs to be straightened out a bit.
Mother's ear(?) (VS sprite) is way off balance. It would normally not be seen (be in her hair)
Mother's face (Trainer sprite) needs some work, specifically the eyes. Look at Nintendo Gym Leaders and other Trainers for how to get the eyes to work properly.
Hope that helped =D