Yea, swap Aquila Cuirass with Firebird.
I thought F+R procs on resource-generating OR resource-spending. Disintegrate is resource-spending. If that is not the case, then swap F+R with SoJ (with bonus Fire damage) + Unity (assuming companion has Unity and the invincibility companion piece). Or pull RRoG off of the cube and onto a finger with either SoJ (offense) or Unity (defensive option) and toss something like the Cameo in the cube slot.
Between Goldwrap in the Cube + Boon of the Hoarder and the 6 piece firebirds set, you should be good defensive-wise even without the Cuirass.