I've been really pleased with Amazon brands for affordable work basics. I feel like the quality is a little better than my usual Old Navy or Target stuff, and I can find actual basics without sifting through piles of stuff with ruffles and peplums and frills (I'm also a jeans and cardigan girl). Lark & Ro and Daily Ritual have both been awesome: I can vouch for this top, this dress with pockets!, and these ponte pants. I'm a size 16 and the XL has fit me great in everything I've tried so far.
I also struggle with shoes so I'm here to pick up tips for those!