The anime has so far mixed the beginning parts of most characters into the first three episodes: The encounter with Satsuki which lead to Yuuki's final decision in participating at the election, one scene of Michiru following him and Chisato when she went with him to talk with the other clubs. That leaves Isara and Mifuyu, whereas the latter has only a few scenes before it goes too deep into the drama-route.
I cannot remember if the scene where Yuuki cooked for Hazuki counts already as another snippet of Satsuki's route or happens also during the common one, but the sisters' argument counts likely towards it..
Corrections are welcome.
@election: The final stage of the student president elections was indeed an important part towards the end or 3/4 part of each route for at least Chisato, Mifuyu, Isara and Satsuki
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