Would the Canon EF-S 15-85mm f/3.5-5.6 IS make a noticeable improvement on this pic?

I would zoom in a little more , use f 5.6 to 8 , ISO 800 unless you are printing over 13 X 17 , then drop to 400.
In this case sharpest is mainly f stop and shutter speed .
Crop out the cords on floor and black background .
Get there early and use a monopod .
While the 15-85 is wider and longer - it would not help
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