Suttas in traditional interpretation themselves state that anicca is relevant to us, because what is anicca, is dukkha (because all pleasant states are mixed up with unpleasant in the long term). As Ajahn Brahm says: every moment of happiness is a pause between two moments of suffering. Every moment of suffering is a pause between two moments of happiness.
DN33
Pañca vimuttiparipācanīyā saññā— aniccasaññā, anicce dukkhasaññā, dukkhe anattasaññā, pahānasaññā, virāgasaññā.
Five perceptions that ripen in freedom: the perception of impermanence, the perception of suffering in impermanence, the perception of not-self in suffering, the perception of giving up, and the perception of fading away.
Cha nibbedhabhāgiyā saññā— aniccasaññā anicce, dukkhasaññā dukkhe, anattasaññā, pahānasaññā, virāgasaññā, nirodhasaññā.
Six perceptions that help penetration: the perception of impermanence, the perception of suffering in impermanence, the perception of not-self in suffering, the perception of giving up, the perception of fading away, and the perception of cessation.
Satta saññā— aniccasaññā, anattasaññā, asubhasaññā, ādīnavasaññā, pahānasaññā, virāgasaññā, nirodhasaññā.
Seven perceptions: the perception of impermanence, the perception of not-self, the perception of ugliness, the perception of drawbacks, the perception of giving up, the perception of fading away, and the perception of cessation.
What is dukkha, is anatta. I personally think that Buddha oftentimes meant anatta as no-self in terms of atta, or sanskrit atman. Atta means that even phenomena in conditioned reality have meaning, because they’re “divine” in a way, they’re connected with divine consciousness of atman. An ideal food for papanca and giving meaning to samsaric existence and prolonging it.
What Buddha points to is that no conditioned experience is divine in any way. Hence it is easier to let go of all suffering and even of heavenly realms. Hence we can let go to the very end and realise cessation. I think teaching of anatta is dedicated mostly to samadhi practitioners (and Buddha taught it mostly to ascetics, mendicants etc.).
When you have samadhi and use psychic powers it gives only for cultivation of beauty rather than seeing impermanence, it is easy to start being in love with samsara again, cause it is so blissful and beautiful if you have higher states of mind and constantly direct the mind towards heavenly realms.
But Buddha said that they’re anicca, if they’re anicca - they’re connected to dukkha (cause they will pass and suffering of lower realms and states come back), and because they’re connected with dukkha, they’re anatta, they are not divine, not to be grasped, howerer beautiful or heavenly or pure they are. Hence motivating even further letting go to it’s fullest to achieve real liberation.
It is complementary with seeing conditionality and that there isn’t any permanent “I” or “we”, any permanent thing we can call a self. I think both interpretations help to dismantle all attachments to “self” whether we understand it as permanent “I” or “divine” nature of conscious experience (atman).
If my reasoning is wrong, please forgive me my ignorance and correct me. 
As to Waharaka tradition even tho I consider their arguments incorrect, I must admit they were thought stimulating. However main problem for me is with unfair and dangerous way they stand against rest of the tradition, way of their argumentation, cult techniques and fact that they create more delusion in people minds.