Okay just a few things to keep in mind.
The rotation you have IS up-to-date. That's how you should generally maintain DPS. There's certain optimizations here and there where you won't do that, but it's a good baseline.
As far as an opener is concerned, that is completely different based on the fight in the current raid tier. I don't use potions, and my openers for each turn are:
A5S:
[SSD]>HT>[LegS>BL]>ID>[IR>B4B]>Dis>[BotD]>CT>[PS]>4th>[Jump]>Ph>[gsk]>TT>VT>[LifeS]>FT>4th>[LegS]>HT>etc.
SSD to close because he's small with a large aggro radius. I hold DFD to drop on the snake when it spawns.
A6S:
HT>[delay-BL]>ID>[IR>B4B]>Dis>[BotD]>CT>[PS>LegS]>4th>[Jump]>Ph>[SSD]>TT>[gsk]>VT>[LifeS]>FT>4th>[LegS]>HT>etc.
Normal opener, sans DFD, which I hold to use on the Blaster Mirages.
On Swindler, it's even weirder, since I'll Life Surge the first 4th hit and use two CT combos, followed by HT>TT>VT on Swindler into FT>4th>HT>DFD on the gobwalker that spawns at the north.
A7S:
HT>[delay-BL]>ID>[IR>B4B]>Dis>[BotD>LegS]>CT>[PS]>4th>[Jump]>Ph>[DFD]>TT>[SSD]>VT>[LifeS>gsk]>FT>4th>HT>etc.
Standard opener, except I shift Leg Sweep 1 GCD forward so that I get it in before needing to dodge Hammers, because of how my group handles them. PS on the run, back in before the 4th hit GCD refills.
A8S:
HT>[LegS]>ID>[IR>B4B]>Dis>[BotD>PS]>CT>[Jump]>4th>[DFD]>Ph>[SSD]>TT>[gsk]>VT>[LifeS]>FT>4th>[LegS]>HT>etc.
I hold BL for Blaster and shift Leg Sweep earlier, since otherwise I wouldn't use it until after TT, which feels like way too long to hold a 20s cooldown.
As far as melds are concerned - lots of people ask "what should I meld?" and there's no right answer to that question. The priority order is (generally) ACC to cap, followed by Crit > Det > Sks. Crit IV is better than Sks V, Sks IV is better than Det IV, and other than that it's relatively linear with that priority.
This raid tier is all about doing DPS effectively and efficiently - NOT about burning everything as soon as it's ready. Study other Dragoons and learn when they hold and when they pop and how they DPS different phases of different fights.
//EDIT: OH YEAH AND. It's not a MAJOR gain, but Blood for Blood, Battle Litany, and Internal Release will all affect 1 additional GCD during their duration if you delay casting the buff until ~halfway through the recast of the GCD (if you double-tap ie. IR>B4B you'll absolutely get the +1 on B4B) turning B4B/BL from 8 to 9 and IR from 6 to 7. It's not major, but can help a lot, depending what that 9th GCD would have been.