I am sorry to report that you do look absolutely amazing in 3. Such a shame you don't feel comfortable because you have the perfect body for it, no lumps nor bumps in sight, only grace and beauty.
BUT... there is a but... it is of a very retro in a Dita-Von-Teese kinda way, so maybe the problem is that it does not go with your personality or personal style. So on that, I would fold it, put it in storage, and keep it for maybe a very special occasion only. Once it's out of your sight, you won't miss it.
Of the 3 dresses, #2 seems the most current in terms of fashion. But here again, if it is too fussy for you, it's no good. Maybe the issue is that it is too short? Have you tried wearing it without the scarf, but with black leggings? Even then if it still feels too chic then toss it.
You seem to have a more understated, "easy" style, which is why I can understand Dress 1 has appealed to you so much, with it's sleevlessness, body skimming and A-line cut. If you remove the other two dresses from your closet, now you are left with only this one. And as you say, even though it fits and looks great, you feel you want to update you dress look. So go for it, start looking for a dress that you would love as much as Dress 1.