Another point that seems important in this dyad.
The instinctual compatibility - SEE types are often Sx/So. The ILI should be Sp/Sx, then, which is often the case. So that works out.
Case in point: My personal experience is confusing because I deviate from this standard. My stacking is syn-flow, it contradicts the classic ILI attitude of being "against" that the anarchy-loving SEE Sx/So so loves. I can't enter a total rejection state that triggers aggression from SeFi. I am Sx-level aggressive myself, but not in the right way to attract a mate, being weak in resolute Se conquest matters. I deliberate too much in a mad passive state (Ni) but I know what I want and need (Sx+Sp). This ambivalence is confusing to me and SEEs alike
I figure it will take more self-improving on my side until I can embrace the pseudo-aggressor role, especially through enneagram 8 integration and Te development. Gotta work with what is already there.
Now, Sx/Sp complements So/Sx. The people that wanted to enter romantic relationships with me so far were NFs, the classic So/Sx types. They were looking for ST authority that I had trouble providing, see reasoning above
The only SEE-Se that I made actual romantic plans for the future with was an Sp/So type. Of course, this didn't work out on the long run. Sp is my territory as it's my second instinct, it functions smoothly and anticipates Sp-lastness. After two years, SEE began to bore me to death with an obsessive fitness agenda. No Sx present to cause a spark, SEE's blind spot was undeveloped, so was mine. SEE wasn't behaving cutely either, something that I really like about So/Sx people as they lack the heavy groundedness.
Recap: my internal conflicts around being Sx dominant have caused mayhem within the boundaries of wrong opportunities, including failed duality and NF romantic interests.