right, you only really use swiftcast if you need to, like when you have to move for any of the 3 long casts or if you need to get the slipstream puddle down asap (putting it down 3s earlier means it ends 3s earlier). The one use of ruinIII or ruinIV can be used for weaving it during Ifrit phase.

Also since Summon Bahamut/Phoenix takes a gcd with no potency it's better to use Searing Light after so you get to fit more damage into it. Think the standard opener does it after 1 Astral Impulse for better party buff alignment