Loyalty Tiers For Secret Emotes
Essentially, enable viewers to unlock secret emotes on your channel, only after they have subbed for so many months. Like say someone subs to you for 4 months, and they unlock a special emote. And another at say 10 months!
This will encourage and incentivize people to STAY subbed.
The back end of it shouldn't be too complex. You could have a drop down menu next to emotes and say "Restrict Until Month 4" etc.
Hope that made sense! This thought hit me of yesterday along with a REALLY good idea for my own secret emotes.