You should add

- Crush on Punch/Kick
- Serious Side hops (Afterimages, Ground shake, and if touched ya get blown away and die)
- Maybe Death Counter
- Stabilize (The function to turn off & on falling basically, so like he'll be able to lift heavier things)
- Sleepy Saitama
- Ability to break things easily (Breaking brick walls, Rocks, Vases. etc with a touch)
- Marugori (Make him able to stand if you add him please ;-;)
- Omni directional serious Punch
- Boro's Effects (When boros takes enough damage his armor should break)
- Transformation effects (When a character has taken enough damage they should be tattered)
- Maybe some animations?
Edit 1:
- Saitama Oppai Hoodie
- Manga Saitama (Black and white saitama)
- Manga Cosmic Garou (Black and white saitama)
- Map Debris compatibility
- True Form/Power Saitama (Saitama that does the same damage as true form king)
- Barrage kick?
That's all I got for now, please take them into consideration :D