Yep, the desire for more control seems to be the number one piece of feedback so you're not alone on that! That's cool about your husband! Maybe he'd enjoy the game more, haha. I'm more into electro-optics (lasers/cameras) so the actual particle physics concepts it's based on is relatively low level (1st/2nd year of a Physics degree).
Thanks for the playtest as well, looks like you relied on pressing to switch between modes a lot, which can make it harder to control. Other feedback has mentioned that the scrolling isn't very sensitive, which makes the change in random variations very hard to notice. But thanks for trying it out!