|Edited with Paint.NET|
|Edited with Photoshop CS6|
Instead of using the hue tools to change the color, I used the color change tool in Photoshop. I was able to select the source color and the destination color, then I just painted over the shirts and the colors changed to the relative tone. That resulted in shades that were much more similar between the shirts, but it also removed the artifacts on the tshirt, which was good.
The content aware fill and spot-healing brushes were invaluable in Photoshop, allowing me to fade in the logo on the polo and remove stray hairs on the tshirt. Overall the tools and options available in Photoshop made the process of editing the picture go much more quickly than with Paint.NET. I'm estimating that it took me 1/4 the time to complete the job in Photoshop versus Paint.NET.
My biggest gripe against Photoshop is that they use a unique control scheme. Where most other programs use a "Ctrl+" scheme to enable different options, Photoshop uses "Alt+" for no apparent reason. More than that, the single level of Undo really annoyed me. The "Ctrl-Z" for Undo is still available in Photoshop, but if you want to step back further than one action in the history you have to press "Ctrl-Shift-Z" which is unnatural and awkward. I've been trained to use the keyboard shortcuts of "Ctrl-Z" and "Ctrl-Y" for Undo and Redo in virtually every other program on every computer platform. There's no reason why Photoshop needed to change things (other than Adobe's need to be different for the sake of being different).
Overall, Photoshop has proven to be a powerful tool that can quickly tackle any editing task, but you'll have to learn the unique and arbitrary control scheme of Adobe to unlock the power of the software.