i checked it out - if you go for it, test the regular serum magnesium (under the "M" section - not the RBC magnesium). the RBC test is better but there's less easily accessible research out there (far as i can tell) with healthy control levels, including units, for comparison's sake. if you have $$ to burn could get both magnesium tests for future reference.
go for zinc for sure! i sometimes get copper done too so that i can look at the ratio.
i usually get serum ferritin done too, and b12.
uric acid (aka urate) is an interesting one if you care to spend the money. i do that one fasting, no coffee or anything before, since it can confound the results.
omegas can't hurt but i haven't had them done myself and don't have any numbers for comparison's sake either.
in your cbc did you get a hemoglobin result? just curious.
green with envy that you can request your own requisitions online like that. if i had access to that kind of service locally, i think i would be in business right now.