In a modular context AD is often enough. I would miss my Quadra though with AHD (or ASR?) for playing with a keyboard. another plus for the quadra is logarithmic attack + exponential decay. This is my go to envelope used in every patch. Also like to modulate the decay and attack times, though for me the expander could be half the size, as I hardly ever use the rest.
Maths to me is indispensable for its ultra snappy envelopes, and its general usefulness with the bus, signal input, offset etc. A serious allrounder.
Also have JF in that same 9u, mostly for all over the place movements.
..and peaks in a skiff which I use to finger trigger envelopes or tapping lfo fun.