You mean, other than what the [LISP] tag already does.
Erm, that merely extends the s's in speech, it doesn't change what they actually say.
What I mean is more like...tokens in, for instance, the Goblin raw files pointing to text files in the speech folder that each contain different types of greetings for them, depending if they're hostile or not. Similar to how the race-specific "brag about kill" messages are currently used for dwarves and elves, or how Minotaurs use the lair_hunter_minotaur.txt file; different greetings/goodbyes could be specified for different races.
I.e if a goblin is an enemy of your civ but is currently non-hostile they'd be rude and greet you with, for example, "What do you want, *race*?" or "Keep it quick, I have more important things to do." and on "goodbye" would say something like "Now leave!" or "Begone!" - different types of greetings based on civ relations. Right now greetings are the same for each race (which, as I said, creates a dissonance when hostile races such as goblins are really polite as they're trying to kill you; greetings can be edited but that applies to everything currently).
This being part of the speech folder would make it more modable and customizable for individual races, which would be a great way for mods to add more flavor.
As for the embark message, I haven't played Masterwork but myself I'd rather not mess around with compressed files.
Also I don't mean just removing the "Strike the earth" and mentions of a "Mountainhome" to make it neutral; again, a token could be added for modding purposes to point to a different embark message. The dwarf one is the default, and alternates could be specified in the entity files.