Dear Gap Sntin,
You seem to have excellent grades as both an undergrad and a graduate student. You also seem to have publications, which is very good.
Honestly, the competition is significantly more fierce for international students then it is for domestic, and while much of your application looks solid, you really need to improve that TOEFL. For example, I think Stanford EE needs a minimum score of at least 100. I wouldn't worry too much about the GRE, but if you get that 350 Verbal to at least in the 500 ball-park, you should be better off. So to answer your question, if you ONLY have time for ONE, then definitely focus on the TOEFL because many top schools have a requirement, and if you don't meet the requirement, you automatically get rejected. However, I don't know any school that has a GRE minimum score requirement. My advice would be to focus on TOEFL.
What schools are you applying to, and what specialization? You might want to start contacting potential PIs at those institutions; that can help!
Best wishes,
-DV