I think all INFJs feel an urge to be able to make their insight useful or known to the external world. I suspect e1s will be most inclined to do this pragmatically, wanting to be as useful as they can; e4s will be less pragmatic in their approach, with more emphasis on the insight being understood than being useful (its 'use value' is more about philosophy/art/understanding the human condition for its own sake); and e6s will be using the insight to simply navigate the external world (and relationships) as well as possible (without as much emphasis on that insight providing some product/service for others in larger capacity)? This is just speculation/me thinking aloud here.
[edit to add:] In other words:
e1 INFJ will take pride in insight being genuinely useful (to improving some external situation).
e4 INFJ will take pride in having unique insight.
e6 INFJ will take pride in being a valuable friend/partner.
(again, just me speculating here)
An aside: LOL @ e7 being least common for INFJ. ( ...

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Another aside, if this chart is accurate: I also think it's interesting that e3 is listed as one of two most common for ENFJ, yet least common for INFJ. ...Like that's maybe some indication of what happens when you crank up the Fe. Actually, from the looks of it, JeNi is the very recipe for e3 inclinations (both ENJs are the only 'more common' e3 types). Interesting.