So, the real issue is triggering individual slices to see where they fit, being able to play them. This is probably the closest that can be done, still requires some prep either on the machine or on computer (easiest). Still will not cure lack of incongruent length slices.
If you want it to be an mpc or a 404, it’s not an mpc or a 404. If you want to play slices on a keyboard/controller from a single track, there’s the way to do it.
I agree that this would be a nice feature to have more easily tied to slice machine for use on a single track but I also agree that you shouldn’t expect elektron to do anything about this because, basically, it’s not that kind of sampler. Not because I think it’s better or worse than an mpc, but because DT started as a “drum computer” and only recently gained all the extra capabilities.
At it’s heart, it’s still a drum machine.