I've always thought I'd use delay more if I could just drop it in on a couple of notes easily. A delay engaged with a momentary switch that can allow the trails to decay while bypassed would be ideal. If it had exp. pedal control over feedback and delay time too, and tap tempo, it would be my dream delay.
If anyone knows of one existing anywhere, please let me know. I've tried in the past to get someone to build me a custom blend box to take care of the first requirement, but discussions sort-of stalled eventually. I think it was maybe too difficult for the guy I was talking to, or too difficult to explain exactly how it should work.