Ok, so... i love the story and of course we wouldnt want Tae-chan to do something illegal now. But a time skip would definitely be the best option here. I mean, it ends 9 yrs before anything concrete happens. I mean, so much can change in a single year. 2yrs from now Mai could fall in love with a girl from her class and completely forget about Tae. Or she could simply move from town, lose contact and eventually move on. Most implied endings use such fragile base and want us to believe in magic. Is too frustrating.
So at the very least reward us with an actual happy end so the journey is complete.