what you describe is rather to be expected to be patches (complex patches, btw) than objects.
piano roll is interesting idea, but 64x64 grid is way too small to make it usable IMO. Novation itself went different way that is (i believe) optimal for this kind of input device — Circuit sequencer, where you have a pattern, and you have different views to edit note velocities and note lengths. piano roll on 64x64 grid would require too much scrolling for the same task.
there definitely were some sequencer patches with Launchpad as UI device, i did a search a couple of years ago and found several. anyway, they are all patches, not objects.