I wouldn't use cast sequence for something like bloodlust because of the long cooldown and how bad it would be if you wasted them.

Cast sequence tends to double up sometimes due to lag if you press them too fast, which I usually do with earth shock and tremor. *(Tremor on castsequence so the pulses delay for perma fear immunity ,V, ^_^ )

Binding to a different button each is what i would do. Takes up more button slots, but its better then messing up at a later date.