Or, as is the case with Samurai, your AoE combo just isn't that effective. The only two attacks that don't have damage falloff for samurai is Kyuten, which requires Kenki to use, and Fuga, which hits like a wet noodle.
Trash packs designated to be AoE'd (and really mass pulls in general) shouldn't last longer than 20-40 seconds to begin with.
Damage fallout isn't a good argument for poor aoe dps since most classes deal with that anyway (and in the case of BRD, RoD refresh is limited to 30 seconds via ballad). You also shouldn't have shifu up for samurai AoE either. That aside, SAM AoE is pretty solid for a full minute provided you don't use shifu and have invigorate. Anecdotal, but I frequently surpass BLMs and BRDs in AoE during the period where I can, only time where I start to fall behind is due to TP sustain. BRD's rain of death spam is only really accessible for 30 seconds during ballad, and otherwise their quick nock is generally weaker in terms of raw damage when you look at SAM having jinpu up and overall higher damage.
Just to compare, the weakest Mangestu/Oka can be is 150 potency on the 5th+ target...most aoe weaponskills don't surpass 110, and the highest otherwise is generally 130 potency. Fuga>Mangetsu/Oka is also more kenki per GCD spent compared to Hakaze>(Shi/Jin)pu>Gekko/Kasha, so your only real constraint here is TP.
Nowhere in my post did I say that. If aoe packs are taking that much longer to die, then the issue lies somewhere; either being undergeared or the other dps not aoeing (or the rare case of spamming Mangetsu/Oka or Sonic Thrust without comboing). For the most part there's no "git gud scrub" when it comes to aoeing due to the nature of it, either you are or you aren't.
See, as Sam I go back and forth. I'll do my 2 aoe rotations, use my Kenai aoe skill then my iai strike aoe. I use those til I hit around 100 tp.
The I use the self tp skill, do some single target skills while still throwing on the iai aoe and aoe Kenai as they build. Usually by the time I start my single target game most sruff is low enough to clear out with one or 2 hits. Especially if I have a blm as a 2nd dps, I try to balance mobs hp as I single target them down so the blm aoe can finishes them together.
Rdm I haven't hit 70 yet, but I go back and forth between scatter and my single target white and black. I feel like it just goes much faster that way
Here's the big problem. On a melee DPS, Goad is an absolutely useless skill to have. The odds that you're matched with another melee DPS is rare, and tanks don't ever seem to run out of TP. Add to that melee DPS basically can't run out of TP on single-target Trial bosses either, and the situations in which Goad is useful becomes so rare that Leg Sweep, Diversion and Feint are infinitely more useful to take aside from the mandatory four skills Second Wind, Invigorate, Bloodbath and True North.
The only real solution here would be to drastically reduce the TP costs for melee AoE. I for one think it could easily be halved and it would still be balanced.