I like M indicus trigger better than M niger - as someone else posted, they don't get as big. As far as color, they have more contrast, IMO, than M niger. If you were looking for a colorful fish, neither fish really has it. Maybe consider a pinktail trigger as well? Some of them are pretty colorful.
Give the fish a little time. I had one, and the colors were very nice, if subtle.
Speaking of colorful fish (and compatible with many) do you have or have you considered an Australian harlequin tusk?