Adding more service is a good thing, but it needs to be done in a sustainable way so that people can rely on it long term.
Sometimes cities will make massive changes to their network. By eliminating bad routes they can often find the money to fund good routes. This is a very different situation.
Dublin Bus has added massive amounts of service over the last decade, going from an incredibly deficient bus service to merely a bad bus service, and has in the course of this been able to significantly lower journey prices, due to increased usage.
> It takes years for people to adjust their lives around better service
I think this possibly _used_ to be the case, but the likes of Google Maps have changed that. You'll see bus routes introduced days ago with full buses, because people want to get to a place, they ask Google Maps, and it tells them. 30 years ago, people would take the bus routes they were used to, but today they will take the bus route their phone tells them to take, so introducing new services has become a lot easier.
(This does sometimes have unintended consequences, when routes intended as low-volume feeders get identified by the apps as a shortcut and swamped.)
Great if you can pull that off in your city, but I'm not confident you can. For that matter if you can pull it off it means you are lacking smaller investments many years before that would have resulted in some transport that you could have grown over time to what you are finally getting.