I'm still missing the Lakshmi bracelet, but that doesn't even have any Spell Speed, and with the +40 won't do too much (will shave off 0.01), and I'm sitting at 1255 SS.
With your Sharpcast opener (I got no procs on either opener) I ended up at around 5.7k DPS, with Umbral at 4.7k. When the Foul comes out during the Hearts in Astral after your Sharpcast opener it's also at 4.7k, so the burst is higher but sustained it goes down to the same level, unsurprisingly.
However. With no Foul to cast at the start of Umbral I'm sitting there twiddling my thumbs waiting for the magic mana tick. We can't meld Piety, and Lucid won't be up forever. Thundercloud isn't 100%. You could hold Foul from the start of your Astral til the start of Umbral, but that feels bad, and it will only get worse. Eventually you will get a Foul at the end of your Umbral, but that still doesn't help.
By using the Umbral Hearts opener you will always have a Foul at the start of Umbral that slowly happens earlier and earlier until you have to Foul within 10 seconds of eachother, but by then you can set up Firestarters for it without any issues.
Just my opinion, but I'd rather have a more stable rotation than a burstier opener that leaves you dry at the start of Umbral. I haven't been able to test Susano EX, but on Lakshmi I'm far ahead in terms of DPS.
