How can I liven up run-of-the-mill stir fry? Rice or noodles, onions, garlic, sesame oil, and soy sauce are a pretty standard stir fry base.

How can I liven this up a little? I'm not looking for major additions, like chicken, eggs, etc. I'm looking for ways to make the base itself a bit more... vibrant and interesting: Herbs, spices, veggies, etc.

I've been experimenting with things like anise, fennel, peppercorns, clove, even MSG, but all of these things just seem to reinforce the same old taste I'm familiar with (sorry, I wish I knew taste words to describe it better), they all have similar "vibes" to me. I also tried experimenting with hoisin sauce but it just seems to muddle everything together. Green onions seem to help a little, when very coarsely chopped.

I'm looking for things that can add some new, compatible but contrasting flavors, rather than enhance or bring out the normal flavor, especially (but not necessarily) things that can make each bite slightly different rather than being uniformly blended in. The meat of this question is flavor pairings with onions/garlic/sesame/soy.

(I hope this question is OK here, the help center did suggest that recipe modification questions were OK, but I'm not sure.)
I notice you didn't mention fresh ginger. That's a very distinctive flavor addition that is commonly used in stir fries.

Also, don't know if this counts as a "major addition" [that you aren't asking for], but since you do mention veggies: bok choy, "baby" bok choy (which I think is a different plant from "adult" bok choy), or mustard greens seem like innocuous vegetables but really punch up the cruciferous flavor in a dramatic way. (especially the mustard greens)