you've done an admirable job of the extractions.....
i can appreciate your wanting to do this and keep doing it til you get it right.....and to that end i have a couple of suggestions....
put a layer or two of shadows between the model and the bench.....your eye can tell you where they would naturally be on the bench when there's an object between it and it's light source.....
i would also work with your background color to more closely match that of the girl.....i see a lot of blue there....i took your first image to editing and i felt that i successfully corrected much of the mismatching of colors there by using the selective color function and toying with the blues and cyans.....
a tool i seldom use except in times of great need.....usually a composite...is render/lighting effects.....although i could really use more skill with that tool, it does offer a gradient light source that falls on different parts of the field according to the color values....it's worth a shot.....
keep plugging away at it til you get it right.....it's the only way to master anything.....
peeper
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