have your SP take cascade. Halo is shit. While it is somewhat "padding" good cascade jumps will do more boss / add / spear damage. Last HC kill my cascade did 5.5m damage in 6 min or so. His halo did 2m damage in a 10:30 attempt. Theres just no comparison between them atm on that fight.
Apart from that, you stand in shit too much as a group.