I'm still trying to figure out some truly interactive things to add once I revamp/restyle my website over the next few weeks... but while not DIRECTLY interactive or silly fun, I always make sure to add functionality that is good for folks who have "reduced motion/animation" turned on on their computers. Like my fun little stamp marquee at the bottom of my site that not only pauses where you hover [exactly where it was at instead of breaking and going back to the beginning] those with reduced motion on it moves slower AND I even edited some of the stamp gifs to be slower/more friendly to photo-sensitivity.
Outside of that I mostly just add interactive style elements.. same with adding themes, [you can choose light or dark mode on my site and I FINALLY was able to make it stay between sites.. I think. So far it's worked for me and a couple friends but we all use firefox :p] and then thinks like hover effects. I also have a cute little firework animation whenever people click around. [if I haven't accidentally broke it yet haha]
It's hard for me personally to try to think of things that are fun, charming, interactive, and accessible, because I try to go too big or end up making things that are a nightmare to traverse with keyboard only (┬┬_┬┬) one day I'll get more interactive stuff.. been to busy doing other things.