I'm finding that cold brewing creates really complex & yummy flavors, even with cheaper beans that are very flat when prepared by drip or press. So, bonus there! Cold brew also has me venturing into the lighter roasts (for years, I've considered myself a "dark roast" girl) because you still end up with such a deep, rich flavor, while getting much, much more of the fruity and citrus notes that can get over-roasted away, sometimes. I finally understand all of the hubbub about "single origin" and the cold brew craze. Coffee has truly become something I can appreciate on the same level and with the same nuance as wine. It's fun.
I'm not much for recommending specific brands. If I'm not buying beans at Costco (good choice with Fara, really), then I'm buying them from a small independent (not any in particular, just trying new things and supporting small shops). If you're in Austin (which I am still only vaguely, although growingly, acquainted with), maybe check out Cuvée? They have some sample packs from their roasters that would give you an opportunity to experiment a little. Perhaps their Ethiopia or Guatemala offerings (both a bit lighter, with complex fruit and nut characteristics). Both are great! Forthright (downtown Austin) serves and sells Sightglass coffee, which is great too. Honestly though, I'm surprisingly enjoying most coffees as cold brew. Even a simple old "Organic Columbian Supreme Med-Dark Roast" under the Sam's Club brand is making me happy.
In general, if Sbucks is too bitter for you, go with roasts that are specifically a bit lighter. Starbucks roasts their beans very dark, which is why they get the common "burnt and bitter" complaint.