Less curves is usually better for surfacing. Do you need 7 curves to define your shape?
Can you post your part? Use the Advanced Editor link in the upper right of the input dialog box.
Like Anna says, use less profile curves and then add guide curves (2nd direction). Sounds like you'll have to simplify the excel curves to clean them up. Also be aware of curvature and use show curvature while you simplify them and also when building the guide curves. Also, use Boundary instead of Loft.
In SolidWorks you generally try to get it right, the first time. So you will not really find such tools as a Smooth because they would imply cleaning up a mess you made in the first place. Though it might be handy for imported data, and ScanTo3d can help with that if you are starting from a scanned in mesh or cloud of points.
You could try making a 3d sketch, use convert entities on the curve, and then use Fit Spline in the Sketch Tools though I'm not sure you can convert curve entities into a 2d/3d sketch or whether the automatic Fit Spline will do a sufficiently good job.
Best would be to redraw the curves in SolidWorks with curvature combs turned on (make a new spline with the spline tool and then right-click it and "Show Curvature") it will be the best in the end. Not sure if you can put a relation on your fresh spline's edit points to the curves to help you, I think you can.
Thank you Anna, Mark and Kevin for your advices.