Atalanta Questions

I do not know how Atalante will work on Camelot. I also have her as my main archer but she works most multi-enemies due to her AoE NP. Her NP is a waste on single boss even with her quick boost.

Her first skill gives more stars and boost damage, but it is better used when her NP is up and against multi-enemies so it would rain stars. You need a main damage dealer especially those who can crit hard. Also, Atalante hasn't received her strengthening yet so she doesn't have her third skill at the moment.

1 - She's not ideal as a damage dealer in Camelot since most hard fights are solo bosses and she has an AoE NP, she can set up a crit chain or buff other allies, or if you really want you can always use her as a crit machine since she's an archer and has a high star weight naturally (though there are best options, cat waifu is best archer).
2 - Her first skill increases quick performance, this means, damage, star gen and NP gen from quick cards, it's by far her best skill and i'd suggest levelling it first if you want Nyanta to make stars rain with her NP or boost some strong quick servant. Besides her last skill only gets to NA in the fourth strenghtening campaign (it's not really far away if you REALLY prefer to level it, we should get it around the week after we get Camelot)