I will definitely say 100% Spanish with courage! There are many reasons why I prefer Spanish to Korean.
Because you speak English, Spanish is easier to learn. Since you are using the same letters in English and Spanish, learning the alphabet is to add some accent here and there. For most of the time you spend your first year on studying Korean, you probably only need to resolve these letters and export them. In Spanish, once you expand your vocabulary, you can write it first
Spanish is used in more countries than Korean. Most Koreans use only 80 million people in North Korea / Korea and Asia. The population of the Spanish is 437 million, which is much more. Spanish is more convenient unless you plan to go to Korea soon.
Compared to Korea, many schools offering Spanish courses do not offer Korean, so if you want to learn, you probably have to do it online. Because no one really can talk to people (except teachers) unless you register other expensive services, online makes communication with others more difficult. In the class you are with other students struggling with you. It helps to learn languages and speak more clearly.
These are just a few of the points I was thinking, but there is no doubt that there is more! Whatever you decide, please enjoy learning a new language both in Spanish and in Korean.
In my opinion, Spanish is one of the most fascinating languages. We all have a willingness to learn certain languages such as Mongolian and Finnish. Because we are especially interested in whether we have friends. Perhaps we want to learn Korean and for various reasons we can see Korean TV dramas and Japanese amines and business. Spanish is different: learning Spanish has many great advantages. I still remember sitting in Marbella in southern Spain. They were closed on the street and there was a table in the restaurant. It is 11 o'clock in the evening. We are sitting under the starry sky. We can smell the scent of jasmine around us. We have dinner at 11 pm. You should not do this at home. The time seems to be stagnant. We are eating this delicious meal, that does not matter. I think the Spaniards have the ability to live in the moment and enjoy it, so that is what you enjoy there.
In my ten years as one of Jehovah's Witnesses, I experienced congregation in four different languages. Two English, one Spanish, one French and one Korean. I spoke French and English, but thanks to these congregations I learned to speak fluent Spanish and a little Korean. At the end of the first two years of my visit as Jehovah's Witnesses, I got married in New York, married someone I met before becoming a witness, and eventually became a person. After we got married, we went to a conversation speaking Spanish. There, everything I knew at the first meeting was gone.