What should Branagh adapt next for the over 60s Saga audience?

after a promising start (MOTOE - the most famous of the Poirot novels) enlisting big stars (Depp, Dench, Pfeiffer, Dafoe, Cruz) and big box office (102m domestic/352m worldwide) the second (covid affected) movie was seen as a step down both in stars (Gadot, Hammer! Bening, Brand!) and box office (45m dom/130m ww), now the 3rd is surely the nail in the coffin with a near tv/stream movie level cast (Dornan, Yeoh, Fey) and horrific box office (18m dom/40m ww thus far)

one ponders what is next for Branagh and Poirot - dare he go the stream movie route with even lesser names, or does he jettison any plans to adapt more novels for something else entirely to appeal to the over 60s audience.. after 3 movies of declining success one must surely deduce the latter is the most likely outcome.. but what? more Shakespeare adaptations? (meh), classic horror? (perhaps reignite the Dark Universe more faithfully with period set adaptations of the iconic characters), a new faithful adaptaion of Dickins Christmas Carol? (with Patrick Stewart reprising the role of Scrooge along with a host of A list british talent)..