Is phainon worth investing in?

His current team is, sunday, dhpt, and bronya. I stopped playing during cerydra's release so I wasn't able to get her. I do want to get her now but I also want phai's s1 so firefly can have the herta shop LC again.

If I'm lucky and win my 50/50s, I should be able to get both cery and his LC but I'm just worried he won't hold up in 4.x (I have trauma from acheron).

Does it seem like he won't fall off so soon?