All speedster in DC!!!
I don’t want to nitpick because holy cow look at all these precious babies and you even remembered John and Dani, but there are a few other speedsters in the DCU:
Joanie Swift, a golden age speedster who accidentally used Johnny Quick’s speed formula while typing it up. She was only seen once because Johnny hid which formula gave her speed.
The Rival, the golden age reverse Flash.
Doralla Kon, a silver age speedster lady from another dimension who only had two appearances, but they were both really good because they were less HOLY CRAP A GIRL WITH SPEED BETTER SHUT THAT DOWN like Joanie’s only story was, and more holy crap! She’s also a scientist, I made a new friend! I personally believe Doralla’s positive portrayal in the 60s paved the way for lady speedsters like Jesse and Jenni in the 90s.
Blue Trinity and Red Trinity, speedster teams from Russia. Christina was part of Blue Trinity.
Speed Demon, a scientist whose wife cheated on him with Wally West back in the 80s.
Sela Allen, who has the coolest design of any speedster ever. She’s a conscious manifestation of the Speed Force.
Impulse II, another Speed Force energy being from the far future.
Black Flash, who is literally speedster Death.
Trajectory, a precious fridged lady who appeared in 52.
I know there are some more, but I can’t remember them right now.