i think its important to judge a bgm together with the show it is used in, which strongly affects the type of the music, in sad moments you will inavoidably get boring music (with slow piano etc). And its also the director, from whom the composer takes instructions as to what type of music to make, so the composer isnt the only one to blame.
Hopefully the full thing will contain none boring music too :)
Question: The drama is going to air in episodes or it will air as a whole ?