Autodesk sketchbook Pro is another great alternative to Photoshop. I'm not sure on price difference, but I like it better than my experience with Photoshop. all in preference, another that people like to use is Sai Paint Tool (?) it makes nice clean, crisp lines, not as easy to figure out in my experience an alternative to that would be firealpaca, which is free. However, like ShadowWings-Forever said using a pen and certain techniques will give you an almost exact feel (and for some artists even better than using a computer program, all in the wrist and experience!
) Also if you do go with Autodesk check out Paris Christou (I don't know how to spell his last name he does toonbox studios on youtube) he has an amazing tutorial on chrisp clean lines for the program
Also, it may not be program settings you need to look in, it may be your tablit/pen settings.