I will have to respectively disagree with your use of Spear for DRG bit at least.
Ninja Abilities
-8 Damage-based Abilities (11 in total)
-2 Damage-based Cross Class Abilities (6 in total)
-2 Damaged-based Abilities 30s and Under
-4 Damage-based Abilities 60s and Under (one is cross class)
-8 Damage-based Abilities 90s and Under (two are cross class)
- Ninjutsu (20s)
- Jugulate (30s)
- Assassinate (40s)
- Internal Release (60s)
- Sneak Attack / Trick Attack (60s)
- Blood for Blood (80s)
- Dream Within a Dream (90s)
- Duality (90s)
- Featherfoot (90s)
- Keen Flurry (90s)
- Mug (90s)
- Kassatsu (120s)
- Mantra (120s)
- Second Wind (120s)
- Shadewalker (120s)
- Goad (180s)
- Smoke Screen (180s)
Dragoon Abilities*
-8 Damage-based Abilities (10 in total)
-2 Damage-based Cross Class Abilities (7 in total)
-2 Damaged-based Abilities 30s and Under
-6 Damage-based Abilities 60s and Under (one is cross class)
-9 Damage-based Abilities 90s and Under (two are cross class)* I didn't count Blood of the Dragon or Geirskogul since you're gonna be building your rotation around 100% uptime on those abilities and Geirskogul you'll probably never want reduced recast.
- Leg Sweep (20s)
- Jump (30s)
- Life Surge (50s)
- Internal Release (60s)
- Spineshatter Dive (60s)
- Power Surge (60s)
- Blood for Blood (80s)
- Bloodbath (90s)
- Featherfoot (90s)
- Keen Flurry (90s)
- Mercy Stroke (90s)
- Dragonfire Dive (120s)
- Foresight (120s)
- Mantra (120s)
- Second Wind (120s)
- Battle Litany (180s)
- Elusive Jump (180s)
Ninja 30s AbilitiesTotal either 456 or 576 Potency +10% for raid damage
- Jugulate (96 Potency)
- Raiton (360 Potency or 480 if Trick Attack is up)
Dragoon 30s AbilitiesTotal of 448 Potency or 563 Potency
- Leg Sweep (149 Potency)
- Jump (299 Potency or 414 if Power Surge is up)
Yeah, I like the idea of Spearing DRG because even though the potency is slightly lower, DRG has a lot of 60s abilities that you'll probably end up reducing as well at times and Assassinate for NIN is only available when the target is below 20%, giving even less abilities to Spear off on NIN.
While there is merit to consistency with Raiton versus Leg Sweep, I do like the odds of me getting Jump and Jugulate as well in a single Spear.