Thanks for ideas, everyone!
To answer a couple questions, I suspect I will mostly wear this to work, since I don't have many dressy occasions outside of work. My social life is pretty casual! A lot of my other dresses have been donated/consigned because they're too loose, and a couple of the ones I've kept for now only look good with toppers because they're getting loose around the arms. So it's nice to have an option that I know fits super well.
I do think this will be a year round piece for me, and it will work especially well with my fall/winter clothes. I have a couple black blazers, one of which would probably work well with this (it's a shorter one), but they're both too warm for mid-summer here. I'm trying not to spend more on summer clothes at this point. I feel like I have a couple options that will make this work for now, and I also know a couple things I might want to get when I start shopping again (cropped, non-sheer cardis, one neutral and one bright).
unfrumped - The seersucker blazer is a recent BR factory purchase. Along with my dress, it was pretty much my last splurge until I start buying for fall (assuming I don't have an emergency need to replace something in the interim). I got it in the store, and can't find it on the website, so it might be a holdover from past BR seasons? I really like that it has only one button, and that the fabric has some structure without being too warm. It's pretty much perfect for my work situation (arctic a/c, casual dress code with more formal expectations for management). I can look a little dressed up without being too corporate with it.