Silly me, after declaring my first test a failure, i went back into the raws and changed several things.
pixies lose WOOD_PREF, so now they can build chainmail, but now i lose all the cheap wooden stuff that i can bring on embark. not a biggy.
gave them the enormous corkscrew trap components, i just realized that my pixies didn't have it, and having to import one makes moving water/magma around a bitch in the meantime, so i just gave it to them.
removed merchant nobility, so now i won't get an outpost liaison AND a guild rep. Just a guild rep.
changed the pixies active season to spring, in a devious ploy to get them to arrive sooner, and thus usher in the human and dwarven caravans sooner so i can cut the necessary playtime to test in half.
lastly, and most importantly, i removed their PROGRESS_TRIGGER tags, because the original dwarves didn't have them, so i suppose the civ controllable race isn't supposed to have them. i also added PROGRESS_TRIGGER_TRADE to the dwarves, now they have it just like the humans and elves, and i can only hope that it works.
what were the results? Pixies didn't come in spring, so that idea goes out the window. I still don't know the effects of the PROGRESS_TRIGGER tags, so i'll just have to change my pixie's active season back to winter, regen, and do another two-year test.