Once you create this safe environment where Senior is there for difficult moments and everything is under your plan "that I know what they're going to fail on."

Once you create this safe environment where Senior is there for difficult moments and everything is under your plan "that I know what they're going to fail on." you will create greenhouse plants that cannot survive on their own. In addition, you will get distracted from higher value work. In my current role, I help 10-15 people weekly across multiple teams and domains. After a period of time, I discovered that it was a mistake. I can see that their's personal grown is limited, they would more likely lean on domain expert instead of becoming expert themselves. Now I am tired and distracted, partially because of lack of seniors.