Herofy Teacher.
I think you and I might have talked at least once about the idea that Teacher is supposed to be a riff on Hugo Strange, but let me float something else. I was recently reading up on the lore of the original Ultimate Marvel universe in order to make sure I wasn't talking out my ass with that recent spate of Ultimate Marvel Posting, and you know whose character bio started ringing a hell of a lot of Teacher alarm bells? Professor X, who, in the Ultimate Marvel continuity, was a through-and-through manipulative son-of-a-bitch, subtly mentally adjusting the X-men as needed in order to keep them a cohesive unit; cavalierly brainwashing, mindreading, mindwiping and personality rewriting in the name of the quote-unquote greater good. A real piece of work!
And with that in mind, you can sort of see a shadier Protectorate department taking a slightly differently aligned Teacher on as their unofficial internal ombudsman; using his power manipulation and personality sanding in a "pro-social" manner to reign in and smooth over internal conflicts, tweaking untoward or regrettable personality traits. This is a version of Teacher whose ambition isn't so much absent as it is differently directed- he doesn't want to build, he wants to garden. He wants access to and influence over as many parahumans as possible, not for the sake of some grand personal project, but for the sake of the PRT's project- sanding down the rough edges of parahuman integration, making everything and everyone operate as smoothly as possible. He's not going to do anything untoward with this influence, of course. Why would he? All he wants is for everyone to get along and be their best selves (as defined by HR and the marketing department.)