I think others might have said this, but DESIRE the way you mention it is already part of every theme. What i want. In the case of desire as a Concern, that means the story pivots on desiring itself, not that a character has desires. It’s not “the mc desires (a car)” but "desiring causes problems for the MC_ " and the MC’s life has to be upset because they desired in the first place, and they have to get over it or hold firm to the desire though people try to knock them off that hill.
@kirro05 I put together a little book related to finding your quad. Take a look at this and see if it helps you figure out which quadrant your story is in (upper right/lower left), and possibly even which domain each is in.
But first figuring out the set of four helps you identify which of THOSE the RS most is like or the IC is most influential in might help you figure it out.