And I can agree with everything you've written -- And I do agree about the 'sea of black' looking funereal with the occasional navy and charcoal not doing much to relieve the somberness.
A few words on being different -- or rather on standing out versus blending in.
- If you're a strong candidate, standing out visually as well as on paper can work to your advantage, providing your visual 'stand-out-ness' is within the range of appropriate, and that you carry yourself with confidence. So maybe a deep wine or dark teal suit, a jacket in a fabric that compliments (vs. matches) your dress, an accessory item that doesn't disappear, shoes in a non-boring color or with a tasteful embellishment. But do bear in mind that if your interviewer is not already disposed to viewing you favorably, this tactic can backfire.
- If you're very tall, wearing heels can make you stand out in a very good way. Too many tall girls try to hide or blend in rather than standing tall and carrying their height with confidence. A tall woman wearing unapologetic heels looks fabulous! Confident. Strong. Capable.
When you say you are "bigger" (such a loaded word) I'll assume you mean you're not model skinny in addition to being tall -- I'd suggest a dress suit. (I know, I know -- I say that all the time. It's such a great look!) A nice dress suit (sheath dress and matching jacket) simply takes your body 'out of the equation'. Whether skinny or heavy, boyish or curvy, a dress suit tends not to show your shape white not being baggy or dowdy and generally looking flattering on most figure types. So long as it's long enough and not too tight, you've got the professionalism angle nailed. And also just a bit different from the sea of suits while being absolutely appropriate and tasteful.
A few samples (shown in less-appropriate colors just to show the design):
Amazon product
Amazon product
Amazon product