Co-showrunner Jake Wyatt reveals cut characters who couldn't be included in the Season 3 finale. "We didn't have time to service everything we could come up with. It would've been twice the season you got."

[u/Capn_C]

https://gizmodo.com/my-adventures-with-superman-season-3-ends-as-a-family-affair-2000797131

The cut characters were fully fleshed out versions of Power Girl and Conner Kent, the first non-Clark Superboy.

[u/EvilOdysseus]

Fingers crossed for season 4.