Let's see:

- Hide & disengage be changed to be actions (as per 5e rules)
- Cunning Action (level 2 rogue feature) to be reworked to include hide & disengage (as per 5e rules)
- Cantrips no longer causing surface effects in addition to causing damage and having their 5e damage values restored
- Monster HP and AC values closer to their actual MM stats

That's it for me basically.