Some synthesizers use more complex envelope generation. That is (DAHDSR, for example): note on - delay (no sound, what you need indeed!) - attack (volume rises) - hold (volume remains at maximum) - decay (it decreases) - sustain (it stops at some level) - note off - release (volume ramps to zero). But there is no standard cc (maybe NRPN?) for delay, hold, &c additional phases adjusts, they are properties of the "program", of your instrument (be your instrument like this).
Yes, "delay" seems be usefull.
The difference between decay and release phases is that the "decay" appears anyway after "attack", and sound may be sustained after that (even at maximum, in this case decay parameter is meaningless) or may become silent (so no release phase be) - depend on "sustain" parameter, but the "release" appears only after note-off and allways go to silence.