Since coming back from my previous trip, 25% of the participants in those classes have been in contact with me by email and one (who had good spoken English skills but won't be able to take this next set of classes) has offered to act as a tour guide on my post-class day of being a tourist, maybe get some of the other students together as well. I think I'd like that better than getting stuck on a group tour as I don't do well with those (I'd rather set my own pace, spend less time listening to sales pitches, and the tour guide last time rubbed me the wrong way [there are some things are better left unsaid, including nearly everything that came out of his mouth]; I'll have a better time with someone I know to be respectable). I've also been shown some talk about the previous trip on the Chinese social media which I can't read, but apparently I made a good impression over there.
One of the classes that I taught last time calls for having prizes available to give out and I brought assorted rubber cosplay ducks which went over very well. I also gave out a few to staff at the venue and one of those was put on display in the classroom before I left. It will be interesting to see if it's still there when I go back.