1) Won't happen, as is not an intent to have "lossing scene" mechs in the game.
2) Amelia has content, others more popular have more but this is mostly an early minigame to get some money and advance Amelia, as most her interactions are via the Wednesday invite and then the beach scene.
3)The characters pairing for something after is being thought out, but for now is mostly just an enjoyable minigame, not for everyone as some people dont like it or find it tedious, but theres a lot of players that love it.
4) There's no need for this, as it would be the same, and you ARE the mc thats training, no changes of view are really a goal. The gym share with Phoenix could have more to come, but not in this way.