its up to your political power actually the stronger your faction power the bigger the value, if you ask me why its require such big value, i used it for counter other negative effect value come from different religion and other else. There are essence of gambling here, some may like you and some may hate you. But its better than everything hate you like usual right mate ?
Now its up your luck , you can even build alliance now as Hun, at least its better then "everybody Hate Hun" policy. The effect will greater on minor faction, half for major faction , its will depend on their status like or dislike empire.