BlackNilton
i think you need the time skip. 1 the age of the mc ( and the other character) are too young. this limit the development and what you can do 2 the young Sheldon don't have many plot you can use to develop the story ( more teen comedy) 3 you can use this time skip to hide the training of leonard and do some flash back when you write some action or scene of comedy with the other character in the big bang theory. 4 you will be more free in the development with adult character and environnement in the start of big bang theory
How about you ReStart .. make minor changes as you see fit with smaller goals in mind like goal 1 his first fight- work the story towards it BUT ...keep an end goal clear where you want the story to go, or else you'll get stuck again. Ask yourself small questions like will he build an organisation ? if yes then what kind , how many members plan everything Ready the skeleton before you start writing so you'll have a clear path to work towards. if you just go with the flow without any plan then you'll get stuck after writing a few chapters again.
my suggestion is skip that week where paige is away & show the trainings results ( or just for now some little parts) when she is back in training the 3 together from there the big skip with some slice of life chaps leading up to start of college maybee with some minor goals like a new mission & that visit at apple the character interactions are enyojable i think the story is currently in summer therse certanly a summer fest, harvest fest, christmad, valentine who could get some nice chill chaps its a good novel that i like even if i kinda wish i would have found it a jeahr later cuz binge reading ^^
My suggestion would be you going with the timeskip the age of the characters aren't really working in your favor you could do a recap on how the MC got close to his girlfriend and how they made a business to grow the organization financial side of they can recruit people from shows that is underrated in my opinion like having some of his people work as consultants get Patrick Jane to join them from the mentalist and Jack Hodgins from bones both would be very good help to them and lastly Elliott Anderson from Mr robot would fit the bill with them just need to help him work through his mental health
You can try and find more people to join the brotherhood like if someone had their family killed by some rich kid or some gang leader's son or daughter and they bribe the police to cover their crimes I bet they can look for people like that to join them. They can also find out there is a secret origination in the world that wants to control the world in the shadows similar to the templars but not the same. they can also try to set up different chapters like in France, Germany, Japan, China, Russia, and Brazil. plus to try to grow the brotherhood there are a lot of homeless vets he can try to recruit. He can also try to go on the dark web and search for evil people like pedos and gangsters to kill. He can also try to find good politicians who want to try to take down crime and help the people like in the games. He can also create a company for the Brotherhood so they can go all over the world and he may have a lot of money but this money would only be used for the Brotherhood. If you want more you can just ask and I will give you more ideas.
I think you should first decide whether the story will be a slice of life or an action thriller. The world of young Sheldon is pretty peaceful, and the drama is quite mundane, so an intense MC feels odd since all the villains he faces are just regular humans. Honestly even if he didn't have the assassin's creed system he would be pretty OP just with his future knowledge of the stock market.
Many of the comments are good, I don't have much to say, except for the fact that you can write more development with the advantages that already exist, if you add too much to the character and it is not used too much it will be merely decorative. For example, he gives importance to the technology he has, it is true that he should not start any business due to age and realism, but since he has tools such as the computer he could have his own dark web or something like that where he intervenes in different aspects of the world. If you do the time skip it would be better because then people will be more dependent on the internet and its networks with which the main character would have information available
Since he’s a genius and has been investing , I think the next step would be him in the shadows implimenting new tech into the old devices or setting up a company that does microchips etc. then for assassinations I think the system will now be the one to dictate the assassinations which would probably be off criminals like real world serial killers of unsolved cases, I think from the real world you can use unsolved cases as a way of not running out of ideas. The best implementation of this I’ve seen is Swarm the TV series based on real life murders but they put their own character as the murder, so you just need to source that information , make up a believable character that performs those cases
I'd say go directly to them starting at university, then do a small, quick arc about what they study, some achievments and recognition in their field of study, comparison with sheldon and teasing him about being the 3rd smartest person in the house whenever he and page comes to visit. Perhaps make some friends or connections at the university. Show how Lennards life changes with his boost in confidence, maybe it makes him a better scientist?