They do make a difference but the only sour spots that can be capitalized easily on are jab, f-tilt, up-tilt, and up-air. For me sour spot on anything else is useless.
F-tilt can lead into dancing blade or dash anything.
Jab can lead into grab, dash anything if they di away and at mid percent, dancing blade, short hop nair, short hop fair, short hop up-air at higher percent, or itself.
Up-tilt can lead into itself, short hop up-air, short hop fair or bair depending on which way they di and where you hit them, rar bair or fair at higher percent, nair, and if you want to even dancing blade if you jump before hand.
Up-air can combo into itself longer if you can get the sour spot, fair, bair, nair, even dair if you get a air dodge read, and if it was a short hop sour up-air it can lead into jab or up-tilt. So really it's less of what works off of sour spots and more where your opponent di's and how fast they can attack out of hitstun.