I like idle games, I really love idle games with a story, and yet this game just doesn't feel like as much fun for me to play, and I think I know why that is now, or at least I've got a better idea. Maybe it's just a me problem, but having to keep repeating the same girl's story while looping to get more MOL to get upgrades so I can actually push deeper into her route just isn't for me. I already know your story, just give me the back half please.
On a more purely story side, I'm afraid the main plot's focus is on the weakest girl in the roster, though given she's gone for most of the route and her stats are a waste of time until WAY later in the game, of course she's getting practically no character development. so now you want me to go focus on running across the globe rescuing this "childhood friend" I barely even know, rather than hanging out with these nice and surprisingly deep girls right at home? No thanks dude.
Honestly if you end up implementing some secret cheat menu like you did in saviors, I think I'd come to love the game a fair bit more, since while the weird life strats to pull off challenge runs for new upgrades is an idea I agree with, the grinding for ML to make those challenge runs viable is a lot less-so