(Here is a modified version. For some reason, the first one couldn't be created more than 6 times in a patch without GUI bugs)
ADSR3.pd

I'm going to use your technique of using a lopass filter as a timing/smoothing object to make an enveloppe detector.

Hi!
Here is an ADSR I made.
You can set the curve (from exp to log) for each step.
Lots of cool options!
It works with short time settings.
Vanilla compatible.
More info on top of the (very ugly!) patch
Thanks

ADSR2.2.pd