Phase cancelation between different audio tracks is an issue that cannot be solved just by a constant phase offset. There are sweet spots, but no matter what the global relative phase of two tracks is, there will always be some frequencies interfering destructively, while others might become too dominant due to constructive interference. I've found that this is the major factor, why two instruments mask each other when combined. As the phase relations change over time, there is also an inconsistency in the timbre, which I don't like.
So I wonder, if there are strategies to somehow even out the intereference effect. Is there a plugin to manipulate phase as a function of frequency... just like an EQ, but for the phase instead of the amplitude. Is there a plugin to define a desired phase relation and have the phases a different tracks aligned automatically for each frequency band? That would give interesting options: A phase offset of 0° would make two signals fundamentally additive. A phase offset of 90° would highlight the complementary parts of two signals by avoiding a buildup in the regions where they overlap. A phase offset of 0° would subtract the overlap of two signals, which is generally not a good thing, but might interesting as an effect.
Do you think that would work, or do you think the phase distortion would alter the timbre of each track so much that it would sound unnatural?