I am a HUGE believer in tights, mainly because I'm pretty confident of the fact that I look thinnest in dresses. These are my favorites:
B.ella Woolissimo Wool Sweater Tights, $42. I found these online at Lori's Shoes, but locally, I bought mine at the Sockshop (locally, although I can't find them on the site). These are FABULOUSLY WARM for winter. And worth the cost.
E.G. Smith Tights, $24. These are actually at the Sockshop, yee haw. Only tights I've ever encountered that are truly one size without (in my experience) weird sag issues. Plus they come in fun colors.
Spanx Tight-End Tights, $26. These are the best tights I've found insofar as comfortable control top and not sagging around the ankles after a full day of wear.