I miss having more control over the ducking feature, specifically in the delay effect. Changing the current single parameter to a few more detailed parameters would make it a lot more flexible and powerful IMHO:
1. Ducker sense input: [Delay Input | Instrument Input] - this way when the rig gain changes, the ducker doesn't have to be adjusted as well (if set to instrument input)
2. Ducker sense knee: [linear | log | exp] - controls how the ducker reacts to changes in input volume
3. Ducker release: [0..500ms] - controls how long the ducker keeps its attenuation after there's no more signal
4. Ducker sense threshold: [-18 - 0dB] - trigger threshold for the ducker
5. Ducker attenuation: [0 - 18dB] - amount of gain reduction for the delayed signal
BTW I know the ducking parameter is present in a lot of places, but I really think the delay effect deserves more control over ducking, even if for that a new delay type needs to be created.