How to justify pulling for her?

I got the itch to pull

To start off im not a whale by any means, I get the monthly pass regularly and that's it. I saved after cartethiyas S3 with BIS team and then directly pulled for s0r0 lynae and s0r0 mournye but did get carried away and got a s6r1 aemeath. Ever since hiyuki leaked im having this urge to pull for her badly but then keep thinking maybe denia would be better for my aemeath to min max her potential. I dont have any other tune break dps as my teams are currently as ;

S3 cartethiya s0r1 chiacona s0r1 chisa

S6r1 aemeath s0r0 lynae and s0r0 mournye

I might need a 3rd team preferrably with hiyuki but then I dont know how to make sense in my pulling priority. If I get hiyuki i might miss denia because I only have 13k asterites and no guarantee at this point.

Whats the best route to build a 3rd team for TOA?