With any customer facing job, you going to find someone who maybe tired, not having a good time, probs at home etc and not smile. Do nto fly 1000s of miles and get upset as an IO did not smile and bow down to your Samsonite luggage, fresh faced look and buttoned down shirt. and your Western European roots.
Expensive watch, bling bling and Samsonite hand luggage make arrival easier? Why are female IOs difficult ? i have never found that in my years of visiting LOS. Why would an IO prefer to welcome a quality Indian tourist over a "quality Western European"?
You need to show 500k THB as evidence of financial stability and ability to support yourself whilst in Thailand. Your school enrolment is evidence of permissible activity.