You forgot to add a vignette filter :) Also, the vignette preset for the curves filter is a bit over-the-top, you may want to get a smoother preset (the vignet

You forgot to add a vignette filter :) Also, the vignette preset for the curves filter is a bit over-the-top, you may want to get a smoother preset (the vignette filter can import Photoshop preset files, so you can look if you can find a free preset somewhere). Alternatively you can find out strategic keypoints within GIMP and translate them to FFmpeg parameter (a bit more hassle I admit), but note that the interpolation between points might not be exactly the same.