OMG you could wear a burlap sack and look fabulous (especially since you are a musician and musicians can get away with all sorts of stuff fashion-wise). you look stunning in just a black tank top and a pair of jeans. Because you are a musician, you could probably get away with anything, so you could indulge your fantasies for a photo shoot if you wanted to.
If I knew what you liked to wear in everyday life, I could maybe suggest more specific ideas based on that; here are some general thoughts, at least.
IMO, there's nothing wrong with the "bland" look--I don't think it's bland; maybe you could try adding different accessories? (Bland to me is an oatmeal colored dress that has no shape, with some plain brown shoes, hair pulled back in a severe bun or ponytail, and no accessories to add interest). A statement necklace would change the look of the "bland" outfit, or an armful of bangle bracelets. I'd say a hat could change the tone of the "bland" outfit, but that would hide that glorious hair.
For me, the key to "dressing up" is fit. Almost anything looks polished if it's been tailored to fit me like it might have been made for me. I don't see any fit issues in your website pic, so that's good.
Textures can add richness to an otherwise "plain" outfit. You could try a velvet, or a suede; leather, fur (or faux fur); or any number of other types of textures to add some interest and keep the eye moving to different parts of the photo.
For some specific pointers: even adding a bad ass leather jacket to the "bland" look would kick it up several notches. If you like black and want to stick with it, something in a black suede (or faux suede) would be an interesting top.
With your complexion and hair, a saturated bright color would look amazing. Even the same style tank top in a bright color would look completely different from that black tank. Listening to the song, I would definitely suggest color. Nothing wrong with black; it's just that black is often seen as serious or moody, and the song is light and upbeat which to me calls for color. A strong, powerful color; a bold color. Of course, that's just my opinion, so there is that.
Hopefully, some other ladies can give you some more specific pointers. Good luck with the photo shoot and your career!
