I think lighter drum sounds (or even filtered) for the verse will really help it feel like it's building to something huge when the chorus comes in. (also add some different crashes to introduce each section after the reverse crash)
also the bridge at
1:40
could have an arp hitting the same notes as the chords with a filter moving around to give it a little more complexity behind the lead!
Merci pur ton retour, c'est cool ! En fait, j'ai tenté l'exercice de partir de 2 samples de voix (Chant + contre chant) et de construire le morceau autour... vu ta question, je considère que l'exercice est réussi :)