I never was your "just wear a sports bra to work out gal", but I bought all of these cropped tanks to review for you guys and ended up keeping every single one because I love them so much. If you don't have a big chest I find it much more comfortable to wear these vs a sports bra and another tank layered on top when working out. With high waisted leggings, you also hardly feel exposed as they only show an inch or so of your waist depending on how tall you are.
Free People Happiness Runs tank linked here - this is a Free People best seller for a reason, it comes in almost 20 gorgeous colorways and is so reasonably priced and an unbelievably soft ribbed seamless fabric.
Lululemon Align Tank linked here - the same amazing buttery fabrication as the Align leggings, this top is so well constructed and includes decent padded support so no need to wear a bra. I would size up in this.
Amazon 2pack Tank linked here - these also have pads for support and are so well priced considering you get 2 tanks in a pack. This is pretty darn close to a lulu dupe!! I sized up to a large.