In theory, the Ruin changes made SMN even harder to play. Ruin III is now the new Ruin (FINALLY we get rid of Ruin), while it did get lower potency it is now our filler spell and still 30 potency higher than normal ruin. This change itself will have you use Ruin III(Or Ruin if you will) over Ruin II. This becomes more of an apparent problem when you have CD's to use. If you use Ruin II, you effectively lose out on potency unless you weave CD's and they make up for those 30 potency lost.

Now you not only have to manage your tight CD management with the crazy 60 second window in which you have to Rouse, Bahamut and DWT for max DPS, but you also lose out on DPS if you use Ruin II over Ruin III :^)
Summoning Bahamut should have made Ruin III instant too.
Devotions 2% is a meme. CD should have been 60 seconds or 120secs with 5%. At least it's a party buff now \o/
SMN is without a doubt the hardest job to play BUT I am happy we finally got rid of fucking Ruin 1 after 2 expansions.