Kind of reminds me of the Katsumi stories I commissioned awhile back.
Honestly, she could fight "Ginyu Force" style aliens with different shapes and sizes (and abilities). Then, I guess there's always the chance to have a Saiyan rival as well.
And if you ever go with a blaxploitation route down the road, you could have a rivalry with a "Supergirl" blonde cheerleader type who is also an alien but from the richer side of town. Imagine her shock and horror when the Saiyan girl can "go blonde as well", turning the heat up and becoming many times stronger. This would go a long way in creating a Freeza vs. Goku type dynamic. Maybe the Supergirl's species (whether Kryptonian or not) sees the Saiyan race as prey or something only for the tables to turn when the legendary Super Saiyan isn't just a myth.
Then, maybe 'Supergirl' has a very busty corporate CEO cousin in "Karen Starr/Powergirl" who is even more powerful and who also bankrolls various goons across the city for the Saiyan to deal with. All the while, they're headed by the Amazonian Queen, aka the "Wonder Woman", who is secretly plotting to take over the world with her Amazons.
In that way, these superwomen could function as a Freeza->Cooler/King Cold->Perfect Cell type set of arcs for the heroine to fight through.
Fight-wise, there was a panel from a Wonder Woman comic where Power Girl punches her so hard she ends up in another country. That was kind of interesting. Perhaps you could replicate this by showing someone gets punched so hard, they pick themselves off a pile of rubble only to see buildings with ads in Japanese or something - all the while gawkers take pictures with their phones, realizing they are now in another country. Of course, perhaps the punched person gets angry enough to create a shockwave that destroys all the viewer's smartphones or something before flying off back at her enemy.
Stuff like that could make it seem more epic and in-line with that Dragonball "scouter/TV screen/mountains blowing up" trope.
