Well its just my opinion the priority main characters at this stage should unquestionably be those who he had before he left his old life behind so Azel, Jamie, Shaunna, Liz and Rachel too yet shes the only one of the five i feel has been lacking the romantic focus, really lacking compared to them in all honesty. Its not a case shes lacked story really but its been the trademark 100 miles an hour stuff so shes already made peace with Jamie and bonding again, already got over Hazing angle and happy being a cheerleader and already even done the trademark character requirement of move house at least three times in six days haha.
First off before I get into this further I have no issues with you wanting Liz stuff or anyone else wanting another character before anyone or anything else. I just want to make that clear, and I am not trying to start an argument about who is or is not important.
Ok for the Liz stuff the background story for Liz is a big turn off. She lied to so many people including her on sister about dating the MC (when in fact they never did in the past). It was clear in the background the Liz treated her sister poorly because she was dating the MC, and tried to stop that relationship as well. The relationship between the MC and Liz seems to be an imaginary one that Liz developed in her head. She was just a cheerleader that was obsessed with him. She was the one that made something out of nothing. It seems that the background there is not really anything at all but a girl that was knocked over by a basketball play and carried to the team doctor to be checked out or just another cheerleader. The MC seems to love and care for everyone due to his nature of a person, but I don't think there was ever anything there truly. Maybe I am wrong, but I don't feel she falls into one of the main characters in the game. She is there for the ride since she is a sister of the MC actual girlfriend. In my opinion the main characters are Azel, Ethan, Jamie and Shauna only. The whole story of the game evolves around those four. Without Azel there is no Rachael (the quest barer), without Jamie there is no Liz (the jealous character that causes drama for the sake of drama). Shauna and Ethan (True best friends that would do anything for each other) have the most devolved background story outside of Azel and Ethan (A loving relationship built on family values). All the other characters are side characters in my opinion, they are quest lines or quest givers. While we all have our favorites in the game and would love to see something or more of one over the other, I feel the primary story line of the game is more important then a side conquest of any of the girls. Ethan is clearly there to get drafted and have a better life for his family, then he realizes his true family is something missing in his life and he wants to reconnect with them. The sex stuff is a great filler, as well as the puppet master behind the scenes trying to do something at the school, and some of the client stuff with Rachael. I feel the important parts are the Basketball progression, building stronger relationships with Azel/Jamie/Shauna, and the reuniting of the bloodline family for Ethan. Sure I want to see some sexy stuff with Stacy or Lz or really any of the other girls, but I try to put that into perspective and say what makes more sense to me sleeping with my girlfriends sister who causes nothing but a headache for both of us (just because she is sexy) or build a relationship with someone who has done something for me and didn't expect anything from me like Stacy. Sure girls are throwing themselves at you all the time too, but I feel there is a method the BD's madness here and the Liz story line needs more time still, just like Stacy.
Again not trying to be mean or call anyone out for what they want to see, I just wanted to share my opinion on the topic. I am wanting to add Liz to the harem at some point too, but I don't think now is the time. Sorry for the rant.