Ultimately, there may be no "need" for "you" to bring a melee sub, but with how powerful DRG's have become, it is harder to justify a non-melee sub for most normal events.
While i appreciate your enthusiasm for DRG melee and do agree that it has gained some ground in the damage department, the job still can't really keep up with the higher tier DDs in this game. Especially in endgame situations. DRG used to be one of the DD kings, but that was a long time ago and the odds of it ever being that way again are pretty slim. Yeah, it can still throw up huge numbers xp'ing on Colibri, but so can everyone else.
Ultimately, it's hard to justify DRG at all for most "normal" events, short of "DRG = Angon", depending on how you define "normal". DRG/Melee is just another baseline DD in a long line of baseline DDs. DRG/Mage at least brings something unique to the table.
It's up to you how you play the job, neither is right or wrong. I tend to find that most DRGs who have been playing the job since NA release have stopped trying to prove DRG's worth to anyone. We just play DRG because we love the job.
Anyway, on topic:
DRG has a lot of great options for hand gear, including Homam, AF+1, AF2+1, Askar, Dusk, Hecatomb, Ares... I see a lot of DRGs in Ares these days. I suppose it depends on where your priorities lay in terms of stats on your other gear. I've been using AF+1 over Hecatomb Mittens recently for WS but i doubt you'll see a huge difference between the two.