I would say no. For the same reason that the Dominion or Xindi aren't overused in DS9 & ENT. Only exception is in this case, it's a species that's been around for over 50 years that we still know so little about. So being able to develop them as a thriving society after 200+ years of Trek history. In TOS, we don't get much beyond slave women. I think it wasn't until DS9 that the pirate aspect really came out but that only in a couple episodes. ENT developed the slave women a bit more. But over all, before LD, they were only in less than a dozen out of the roughly 500 episodes that preceded LD. Plus, they have been set up the series villian. TOS had Klingons/Romulans, TNG had the Borg, DS9 had Dominion, VOY had a vast myriad, but considering that they were traveling away from their starting point, it made sense. So I think the amount of Orions in LD is just fine.

Humans are overused.

Agreed with Billwinz, the Orions aren't overused precisely on the grounds that, until LD picked them up, we barely knew anything about them. Heck, even with having Tendi, an Orion herself, in the main cast, even LD didn't really start to explore the Orion as a species in depth until the past couple of seasons of its five season run. If LD's overusing the Orions, then the other Trek shows are by far more guilty of "overusing" the respective species by comparison.

@Fandyllic

In all seriousness, you are absolutely correct--humans do appear more frequently than any other species in Trek. Which, when you really think about it, doesn't make as much sense as you'd think, given that the Federation, and in turn Starfleet, is supposed to be a multi-species organization allowing for equal representation of all participating species...and yet the humans still end up by far the more dominant species, even as late as the 25th century.

One of the Klingons in Undiscovered Country referred to Starfleet and the Federation as a "humans-only club"...I sometimes wonder if there was more truth to that than Trek is willing to admit at times.