1, Move most expensive logging code to the native part to make the Java code clean and more efficient.
Size: Median

2, Implement an independent auto/never snackbar's UNDO operation, which will heavily simplify the Android logic.
Size: Small

3, Create our own *delegate module* for compact UI to replace current translate_delegate which was designed for multi steps UI. And that's also Bubble UI's solution. 
Size: Large

4, Fix the critical missing unit tests for both new and old modules.
Size: Median

5, Once new UI is fully launched, a big cleanup for all the unused code in both Java and native part.
Size: Large