Super cool idea with great execution. It reminded me a bit of WarioWare in that I had no idea what sort of game was coming next and I had to quickly figure out what was going on. The dating sim was an inspired touch, too. I'm not usually one for inside jokes and niche references, but we're all Dunkey fans here so I'd say it was tasteful.
I have two pieces of constructive feedback: the first is that I didn't know that the 2D platformer spikes were spikes until I landed on them. Take that with a grain of salt though, I'm pretty dumb. The second is about the health system (not lives.) I'm not sure what determines how much health you'll have at the start of a level, but on my second go at the 2D platformer, I lost in a single hit.
Overall, I'm impressed by the variety on offer and how polished everything looked and felt given the scope of your project. You've made something really special here, and I have a feeling I'll be coming back to this one soon.