Considering MP management, (no-DA'd SE + Passenger) or (DEL + Passenger) is better than DA SE as it's half the cost & 20-40 more potency - if MP is an issue than following this priority with your Passenger opens up a following DA > SE you else-wise may not have access to.
You can do this every 30 seconds, and maintain enough MP for DA'd CnS every 60 seconds.. This seems to be the best method IMO. Scourge's 30 second duration helps keep track of CD availability too, at least that's how I approach it (at 15sec DP+DEL, 30 sec or falloff DA'd CnS + SE/DEL), ie 2 combos between to risk not sucking MP dry, and allowing that space for DA'd SE as 1 or both of those combos if MP is available