I was going to call out the deluge song mode as having a very solid approach to timeline and dropping clips. You can drop a clip, use its marker to swap to a new one and at any time you can start changing things and it’ll automagically make a new clip with your changes in-line in the ‘arrangement’ timeline.
Hapax would need to implement color coding on the pattern screen but not much beyond that for the concept to port. Obviously the lack of a button and getting priority in the stack are still an issue.