What am I still doing wrong? (Serial Restarting in New Saves)

You like starting things out and setting them up but you need mid-story action. So, make something happen when you get to that point in your story. Use the tools available in the game for that. They have too much money? You can lose some of it; you can use the Money "cheat" to erase money from the household. It's called a cheat but it can be editing to add concepts to your game. An investment could go bad. A character could develop a shopping addiction and spend on frivolous objects or just burn money in the fireplace if you have Get Famous. A child of the family could decide to waste all the money or you could go for a Johnny Zest approach and start over with a relative who was abandoned.

You can come up with other mid-story events or plotlines. I am doing that in my own game. I personally don't mind having some wealthy sims though not all of mine are, I don't get bored when they are well-off. I do have the need for mid-game plots to add to the game. I've done some online research about it and sometimes I just come up with what I want to do next during gameplay. You could make a list of possible mid-game events or mini challenges and then randomly pick from them. I might end up doing that sometime.

Things that I do mid-game to make things interesting include traveling with sims, learning a new skill, adding a pet, adding a child/parenthood, having a party or event, making new friends, making up some drama between sims or just going out to different lots in the world. They do seasonal activities. They go out to my custom lots in the game. They run into different characters both good and bad. You can make or download from the gallery new lots and spaces for them to visit. You could have them develop their personalities more. When you think of an idea of what to do, follow it. Be willing to change the way things are in the game.

- A boy, now a YA, who had a criminal mother was raised by his kind aunt and then made his own way in the world. His childhood sweetheart whom he married is much wealthier than him. Together they want to move to Chestnut Ridge because they both love horses & the outdoors and they want to start a life together where they will both be accepted from different backgrounds. His mother will come back into his life to try to reconnect but she is also a greedy woman and she may try to beg her son for too much money. He needs to figure out whether to let her back into his life and how to not let her take advantage of him or interfere in his happiness and independence. He is also dealing with how he loves his wife but he does not fit in socially with her family and friends. This YA and his wife are some of my favorite characters, so they are fun to play with. To make it more interesting, his mother is going to try to to take advantage of him but he will handle it by being compassionate and then knowing when to detach from her. Still, he will spend his whole life looking to give his children the relationship with a parent that he always wanted. He has the "big happy family" aspiration.
- A military family in StrangerVille is going to be reposted to Mt. Komorebi. They will need to learn new customs and start all over while respecting and learning the traditions of their new home. I will build my own Japanese restaurant on an empty lot that any of my sims can use.
- Two neighbors in Willow Creek are competitive with each other. They work in the same field. One of them actually received a message that he has been blocked at work by the other and he needs to deal with it in some way in order to progress in his job going forward. The one blocking him is a low-level celebrity with a similarly ranked wife who is a professional critic. These neighbors are from very different cultural backgrounds. The one who seems like he is on top is actually struggling to fit in. They need to learn to get along or else the one who is blocked is going to stagnate in his career. He is not a young man and already had a mid-life crisis seeking creativity. Both families are pretty happy and stable but there are underlying conflicts. The man who feels trapped may end up shocking his family by changing his career or pursuing a hobby they didn't expect. Something needs to change in this situation because the person who is blocked at work won't want to stay that way.
- In another household, they seem to have it all. The father rose from poverty to be really wealthy and is near the end of his life in a mansion. His beloved wife has passed away. Now, he has three older teens who are about to become YAs. One daughter, Valeria, has always been his favorite. She is so confidently smart and he has always been closest to her. She is "perfect" but she often feels socially lonely and does not know how to have fun. The second daughter, Ileana, struggles at school but is incredibly popular and charismatic. Everyone loves her. She has a devoted boyfriend who can't wait to marry her but she isn't sure that is what she wants. She dreams of being a famous actress in Del Sol Valley and settling down too early will trap her in a life that she doesn't want. Their brother, Javier, was unlucky. He inherited unflattering looks and has always struggled with his weight. No one is interested in him romantically but he is a nice person. He is often telling jokes and using comedy to deal with his social awkwardness, so he is actually well-liked by many people but he has low-self esteem. Still, he is a great guitarist and wants to join a band. Will he always be the awkward brother or will he find a life of success in which people appreciate him? (He would really like a Bands Pack). How will this family change as they grow up? Their father will not live forever and they are all about to go out on their own paths. Javier might end up being the most interesting character because his future is less predictable, but they will all be enjoyable to play.