There could be a short range of generic signals for common messages, designed to be quickly understood across a broad range of cultures - like "SOS" or "Mayday". Perhaps if this was made less like radio comms, and more like naval flag-signalling, it would help the context and seem less of an immersion-breaker. I'm not suggesting that the ships should fly flags, but perhaps it could be possible to make a virtue out of a necessity, and reveal the parser to the player? Let the player choose from a short list of available words/phrases to assemble a message, which could then be sent as a signal.
A parser in-game for comms might be nice. I actually in Oolite's context wouldn't find a program of text chat macros all that unbelievable, the galaxy has eight separate quadrants with hundreds if not a thousand of worlds each. Verbally using radio to communicate with pilots of an unknown species and homeworld would be a nightmare with all the different languages and cultures, even granting that digital media and globalization have reduced the amount of living languages in the world.
Imagine talking in English as an American or English person to some one with a thick, say Indian (or other non-english speaking country) for example, accent, then imagine it except you all aren't even from the same section of the galaxy, and you as a Lave Academy Graduate are speaking (using proper Lavian Gal Standard or whatever) with some one from a nowhere anarchy in G3, a G5 feudal aristocrat, and a G8 refugee from some corporate state that the current holder of Galcop's military and police witchdrive contract outsources parts from. You wouldn't all necessarily have the ability to pronounce the same vowels and consonants, at least not in the same way, even if you can speak the "same" language. Communicating verbally would drive everyone insane, and might be impossible in combat or an emergency.
Having standardized comm signals with a client side translation into the pilot's native tongue might be a god send, and the closest thing to a universal translator that is reasonably practical (and simple to implement) without requiring handwavium pseudo-science. For example, the TOS Star Trek "reading" brain waves, because of course an alien lifeform with less in common with me than my cats will have a similiar brain structure. What exactly does the brain of a furry blue feliniod-type underperson look like anyways? And how do their vocal cords handle human languages?