Regarding photos for job.
When you look for teaching job in Korea, all agency ask your photo to show school supervisor or owner. If interview is held face to face, photo may not be that important. But since school owner or supervisor can’t see you in person and interview is commenced on the phone, they tend to judge you by your photo. Each school supervisor’s preferred look is slightly different but mostly they want to hire someone who has favorable impression, specially if you apply for teaching young kinds like kindergarten. And your look is not naturally bright then using photo taken taken with your niece or nephew will be compensated for that.
Photo give your the first impression to school owner and supervisor, hence it is always good to use smiling and well present yourself. If you are not sure what photo is good then please give couple of photos to your recuitier, she/he will know what is the best.