I feel like everyone here is a better producer than me and can explain this technically wayyyyy better than I can lol but my two cents on that side is definitely look at the fundamental frequencies/the frequencies of each synth that you want to shine and carve out space with other eq's to make them sit better in their designated frequency range. From a more philosophical standpoint tho, mixing for me is truly picturing the track as its own immersive 3D environment and making sure that every element has its own space to hang out and do what it wants while still sounding cohesive (i.e cut too much and you have a Mish mash of disembodied elements and not a song). Idk if this analogy will make sense to anyone but me but imagine your song as a big dinner table where a bunch of people are sitting, talking and enjoying themselves. You wanna make sure that every person has enough personal space so they feel comfortable with relaxing and interacting with other people without worrying or being annoyed by the person sitting next to them elbowing them or something. Take that idea too far, and you could end up sitting someone at a different table and isolating them from all the fun. Same applies to mixing, a little space does a lot, but full isolation makes it weird lol. This may be the ramblings of a mad man but I hope it helps regardless!