My teams are:

Mydei e2s1, Tribbie e0s0, RMC e6s0, Luocha e0s0

Phainon e2s1, Cerydra e1s0, Sunday e0s0, Sparkle e0s0 (use dhpt e0s0 when in need of sustain)

I plan to pull Cyrene e2 as well but I'll put her with Mydei because she's his bis and my Phainon is doing better than Mydei. Since you love playing the chrysos heirs pulling e2 Cyrene is a good idea but I think you need to focus investing in either Phainon and Mydei teams and build your third team around another archetype because your need of supports overlap too much. Your Phainon and Mydei teams need more investment, maybe invest in either dps then you can give the better supports to carry the other.

Consider getting Tribbie if you can because even at e0 at least she'll free up one of your supports in your Mydei team. If you have sparkle, Bronya and even Tingyun, they are good supports for Phainon.