So I’ve read a couple fics where either Jack or Gabe were shorter than most people in SEP and then got bigger because of the magic science goo, and I love it. But. Imagine if you will:
They’re both shortish to begin with but the same height. Then one of them grows like half an inch, and starts making fun of the other one for being the shortest. But then the short one sprouts up just a bit more. And they keep messing with each other the whole time (over like 6 months/a year however long you hc SEP to have been) Eventually they both end up being really tall and the same height, but the dickery continues for years. One of them will get a slightly taller pair of shoes, the other will grow their hair out just enough to stick up just high enough etc
I love to imagine Steve and Tony trying to go on a date together but having the hardest time of it because they can't find anything to do together that they don't already do. Eventually they realize that it's because they've been dating for literal years and never realized it.