..searching a generative patch

There's a handy patch in 'max extras > examples overview > max' called 'scaler'. It'll play random notes from a given scale in a given key (it uses a coll lookup). You can adapt this slightly to provide the basis of a note generation engine for a generative patch.

Of course though, you'll have to change the midi note number to a frequency ratio relative to the samples own ratio (1) for it to work with your idea... so like an octave (12 higher in midi note terms) would be ratio of 2.

You can then do whatever... load the sample into a buffer and use groove with the note frequency ratio to playback maybe? Otherwise you could build a little oscillator bank with some filters (whose parameters could be randomly selected for each note) and some delays.