Pitched grain feedback would be interesting! I don't have any short-term plans to do this, but it might happen in the future
ADSR is probably the most often requested feature so I think it would be a very welcome addition.
I already did some work on the granular processing that allows ADSR envelopes (and pitch modulation) on grains. Needs some more work (optimization, UI, etc.) before I can release it but this is very likely to be added in a future update!