In my general experience, smoked dmt is much more intense and can take you further away from earth and your body, sending you flying out into hyperspace. Ayahuasca, tends to keep you grounded, as they say it builds a bridge between earth and heavens. Aya guides you on your journey, and the dmt from chacruna/chali/mimosa is like its helper.
With ayahuasca you have time to properly work through stuff, it is a physical, emotional and spiritual healing and cleansing medicine.
I believe Changa is also a medicine, I have been witness to that a few times this year, however it is much shorter and more intense, allowing for quick and deep insights.
In my experience, smoked DMT is more about exploring hyperspace, whereas Ayahuasca is generally more about you and your place on earth, society etc.