I disagree that season 1 revolved around them because of plot convenience. For me they are the main girls because a big part of season 1 was building a proper relationship with them. The main girl/s of porn games for me are ones that we are building a relationship up with that ends in possible marriage and kids. With Acting Lessons I only consider Megan the main girl if we choose Melissa as a friend but I consider both as the main girls if I am building a relationship with both of them.
ALOT of the scenes we got in Season 1 with Maya & Josy were unavoidable and needed for the plot to progress:
Josy being MC's hometown crush and very first girl who we're introduced to who we later find out is Maya's girlfriend
MC staying with Maya at her dorm room when in need of a place to stay leading to unavoidable interactions and scenes with her
MC getting romantically involved with Maya and both catching feelings for each other regardless of what ever options the player chooses.
MC going on a date to Josy's place in which DPC sets up to progress their story line meaning we don't get to choose to weather or not we'd want that.
Josy getting a late acceptance to set up episode 3's ending and everything that followed.
We got very little content for Jill and Bella in S1. Sage however did get a decent amount of content and is the first main girl we've gotten a full and uninterrupted sex scene with but still not as much screen time as Maya & Josy. I'd argue Quinn got more screen time than Jill in Season 1.
Every Main & Side girl are apart of the main plot as they're all connected to one another some more than others and
all are well acquainted and or involved with MC in some way.
If season 2 gives us the choice of building up a proper relationship with Jill, Bella or Sage
It will