Cuero - Yoakum is a good one because both teams stand an equal chance of winning. In any 10 year period it will be 5-5 or 6-4. Never lopsided.
That is why Sinton Taft could never be considered a rivalry. Sinton always wins.
I don't know about Snyder-Sweetwater but I have a friend from Sweetwater and his disdain for Snyder and Abilene Wylie is way greater than anything we have around here. Yoakum and Gonzales included.