Well, a single layer of linen (or cotton) is cool, and I own several long-sleeved undertunics. But they look so naked without anything over them!
Also, I have a growing pile of small beads and ornaments that I've been given at bardics and A&S competitions for my work. I'd like to display them, say... on one of those festoons strung between the pins of a Viking apron-dress.
Which is, hey, a simple sleeveless thing worn over an undertunic! It is an additional layer, but it's about the most minimal one I could think of. Might this be a solution to two problems?
Then there's the third problem: events coming up soon. Sure, two weeks is plenty of time for an unornamented apron-dress for most people, but not quite for my life.
But I do have a blue flannel sheet that no longer fits any bed in the house. I could hem that sucker all around and do a wrap-style dress, where there's overlap at the top so you're not flashing leg at the bottom. I believe it used to be a common way of making apron dresses, although scholarship since then has found better ways.
Pros: Fast; leaves fabric intact for other uses if I upgrade later.
Cons: More layers of fabric over my chest, not the right way to do it.
Likely course of action: Hem the sheet, but see if there's time to draft a pattern for a more fitted single-layer dress.