Choosing between Spanish or politics and society

Hi everyone!
I’ve just finished my BA in English and I was hoping to go into teaching but after attending a career council meeting, I was told to get a HDip and add a second subject for employability reasons.
They recommended that I do Spanish as I already speak Portuguese and so the learning of the language would not be hard for me and languages are in high demand. However after browsing the HDips available, I think I’m more interested in politics and society as a subject, however I am aware that it’s a leaving cert subject only and so I am worried about getting a permanent contract with those two subjects.

Any advice would be welcomed!