The advice for most people in your situation is try something different, to broaden your overall knowledge of the language.
From the sound of it, your strength is in speaking, and perhaps to a lesser extent, listening. That suggests that you are "relatively" weak in reading and writing. In that case, try your hand at say, reading, and by this, I mean poetry or advanced texts, not childrens' stories, or even the newspaper.
You probably have a good grasp of "everyday" vocabulary, For all I know, you may already be at a level of IL4 in "conversation," while having an IL2 ability level in reading specialized vocabulary, for a "blended" IL3 level. If you want to reach the IL4 level in reading and overall, and become a "translator," buy a Spanish language version of an English novel, translate the English version into Spanish, and compare your version with the "original" translation. Or buy yourself a Spanish copy of Samuelson's Economia, and learn about "la ley de oferta y demanda" (the law of supply and demand), and "la teoria de la ventaja comparativa" (the theory of comparative advantage).
I have the opposite problem. I learned to read Spanish, and can read (and to a lesser extent, write) at a "university" level, in math, economics, politics, history, etc. What is my weakness? The everyday stuff that every ten or even five year old knows. The cure for my issue is that I need to "get out" more and talk to people on an every day basis. That is, I may be at an IL4 level in "reading" and an IL2 level (or worse) in other areas for a blended rating of say, IL2.