Have you seen Junko Okamoto's designs? They are so unique and engaging... Many of them are one size fits all, which means you either get a super cozy oversize fit or you can choose to tweak it and make it smaller.
The first one on my list was the Bright Sweater. I knit this with Andean DK from Estelle Yarn, a very very lightweight that feels more like a sport weight to me. With 350 m to a 100 g, it's lofty and has an excellent price/meterage ratio!
I followed the pattern with no mods, except maybe for the lenght of my sleeves. Although I might go back and add an inch to each. The yoke is fantastic. It stays up around the neck without being tight and the mix of cables, twisted rib and clusters keep everything in place.
Ravelry project page, I could definitely knit another one. But then I want pretty much every design by Junko!