Gravel. Yes, you already have an E2 Phantom, but having a second fast-redeploy would help, and Gravel is simultaneously very tanky and relatively cheap to build. Also might recommend building BP or Plat as a subsniper, Texas because clutch extra DP,
sp battery Liskarm would probably appreciate the extra stats, and Bibeak/Exec/Broca but that’s just my bias speaking
Oh and Specter, undying nun go brrrrrrrrrrrr
Amiya/Provence might be worth considering as well, seeing as you don’t have a dedicated boss killer as far as I can see, and one of them will be needed later on (not gonna go into details)
Yeah that basically sums up my opinion
Fill out your specialist, FEater, Manticore and Gravel.
Elysium is extremely good for some fast DP gain and also to support your Physical DPS (Also slow utility is too big me thinks).
Amiya also can be pretty nice to have around, big dmg regardless of enemy RES (she also will gain something special once chapter 8 releases if you have her promoted, not gonna get in details but it’s REALLY good).
Specter is selfexplanatory, fantastic on all senses. Mastery 3 even makes her a super good helidrop unit, one of the best imo.
And for my bias promote Bibeak and Astesia
staller might help a lot so i suggest raising glaucus, feater, manticore, gravel, istina. and specter is a must.