You're dead on except for the ENFP's amazing ability to be manipulative. Don't ever make the mistake of underestimating this potential. I'm not saying all ENFPs are manipulative, just that ENFPs have the capacity to be very good at it - if they choose to. (Also, and this is the most important part, don't assume that because you can see right through this that others will too. They won't unless they are Ni dominant - INFJ or INTJ - from what I've experienced.)
Also, don't underestimate an ENFP's ability to make an assumption (Ne) and assume it is the gospel (Fi) without ever telling you about it. Again, I'm not saying all of them do this, but they have the capacity to be extremely petty and underhanded - just like we have a capacity to be judgmental and domineering.
In my opinion, INFJ + ENFP = Really good if both are good, healthy, and mature people. Really bad if either of them trigger's the other's shadow modes.
For INFJ, Ne, Fi, Te, and Si are antagonistic functions until we learn to master them. When manifested in others, they can be very toxic for us, in a host of ways that encourage us to our worst. INFJs have the same effect on ENFPs who's shadow functions are Ni, Fe, Ti, and Se. However, if we've mastered these parts of ourselves, then the other person can be a real inspiration and cover our blind spots very well.
I have had more than one serious personality conflict with ENFPs. I also have several ENFPs whom are extremely close and long time friends. It all depends on the individuals. However, I've never had an 'indifferent' relationship with an ENFP that I am aware of. There was always some degree of polarity.