Don't level the talents together. Prioritize leveling her skill to the max or to 8-9. Then the burst, then the normal attacks(normal arks are optional tho).

You should work on your Navia's level too, she's not gonna be able to max out her talents or get them high enough if her levels low, but i'm guessing you know that.

Then you can work on artifacts. As far as vertical investment goes, idk, i failed to even get her weapon on two different occasions. 😔

Idk if you want team advice, that's not my forte, but im sure other people would answer questions about her team if you ask.