It looks like a pretty and very healthy Oncidium! I can't tell exactly which Oncidium, but perhaps others here know.
You seem to have its growing conditions well in hand and I would probably pot up the plant into some fresh medium. I would soak the plant first and have well rinsed, soaked medium bark on hand and then place into a new pot with good drainage again.
Looking at those beautiful roots, I myself would be afraid to disturb them and simply pot on.