This tunic might just be that perfect top. It is long enough to cover your bum if you pair it with leggings. It has 3/4 length sleeve to hold in my arm wiggles but not make my wrist warm, because I'm crazy and that happens. Plus it has pockets!!!
Fit advise: This brand actually runs on the bigger side. I typically wear an XL or 1X. The 1X in this was just about perfect. It skimmed the curves I wanted highlighted and avoided the ones I wanted concealed.
1X: Bust 46", Hips 65", Length 30.5"
2X: Bust 48", Hips 67", Length 30.5"
3X: Bust 50", Hips 69", Length 30.5"
Fabric Content: 95% Polyester 5% Spandex