*MY* Ideal-ish Philoise S5 Plotline:
Eloise has been NEETing it up for 2 years(i wouldve done 3-4 year timeskip but wtv), dispassionate and bored now that both Polin and Bendict are living married lives w/children. Even Violet isn't focused on her due to Hyacinth's debut and Francesca' (eventual) redebut.
News travels that Marina has passed. Standard reactions all around, but Eloise happens to overhear the staff gossiping about certain curiosities and mysteries surrounding her death and oddities at the Crane household. Eloise is eager for a distraction from her own aimless lifestyle, so she writes to Phillip in hopes of uncovering some secrets (starting with a condolence letter ofc)
Eloise and Phillip start a dialogue, which Eloise enjoys despite Phillip not giving her any real details on the things that she's curious about. People start to wonder what Eloise has been up to lately (slight LW suspicions begin)
Eloise's S5P1 plot ends with Phillip proposing marriage and inviting her out to Romney Hall
Part 2: Daphne is back! (Yep.) Eloise spends time with her (and violet/ hyacith), plots start to converge and need eloise's presence(time with pen or ben or hyacith or violet or francesca or whoever), so no reply and no time for Eloise to address the proposal
Daphne confronts Eloise after the suspicions of Eloise being the new LW grows. Some tough love. Asks her what exactly Eloise plans on doing with her life, laments on how little she's done even without their mom hovering and urges Eloise to take some sort of control of her life, that she can't just dream and theorize and wish. She has to make a decision for her life. What is stopping her? Eloise assures her that she's not LW.
More plot convergences, Eloise doing other things Franchaela related most likely. Eloise maybe glances at the letter or hides it before going off.
In the last episode Eloise is fully cleared of LW suspicions. Daphne throws a Francheala celebration ball. Gay party. Everyone having fun. Franchaela final kiss. All remaining conflicts resolved etc. Colin (it has to be Colin) looks around, "Where's Eloise?" We get a shot of where Eloise typically keep her letters to Philip, all of them gone. END.