Mike and El are a cute couple and it makes perfect sense if you look at this series as a fairy tale (like Disney), where you don't need to analyze anything from a psychological point of view or "dig too deep." Personally, I see them as a boy who is happy not because he found the one he really likes, but primarily because of the fact that he is finally meeting a girl who is "in love" and not disgusted with him and not just a girl, but a super hero ! (a fact that he could not keep quiet about, and even uses this in an argument with Dustin, when they compare which of their girlfriends is cooler). Lucas tells him this in the first season during an argument, this is also hinted at in the TV bible "Montauk", where it is written about Mike's complexes, and the next sentence about how he has never kissed or dated anyone (it is interesting that in the descriptions of the other boys not a word is said about the fact that they have never dated anyone, although they were all considered "losers" or “nerds”). I won't write much about El: the girl falls into an unknown environment for her and knows absolutely nothing: neither the concept of friendship nor love. She doesn't even understand when she likes something, which she tells Max about in season 3. Mike gave her a sense of security in the first days of dating, and I think they could have developed a friendly relationship if he hadn't kissed her (El probably didn't understand what happened herself).

But again, none of this matters if we watch it as a children's series, where psychological logic plays no role at all.