This thread is very interesting to me. My first set were Centennials. I still love them and think they are beautiful! A great tradition for sure. That said, I like MANY other color and style sets for no other reason than it makes the table more fun. If I'm going to go to a tournament, I like to know what balls will be used and practice with those, but for home and play with friends and family, I like a lot of variety just because. Here is my take on the sets i own:
Centennials - stunning, traditional, play great, IF I could only own one set, these would be it.
Predator Arcos II - I like the variety and these are the best playing set I have ever owned. Others disagree, but I really like them and the colors and the Cat logo are cool. Everyone who plays them on my table really likes them as well. The Arcos Triangle Cue ball is the best in the universe! IMHO
Aramith Tournament BLACK - These are favorites among friends who don't know a lot about pool. They just look so cool that they grab your attention on the table. They take a little getting used to because some of the stripes are hard to determine due to the black background, but they are just so cool that it's worth the effort. I like the black measles cue ball as well.
Elephant Beautiful Balls - These are the marbled ones and they are the favorite of my wife, daughter, and every lady who has ever seen my table. Obviously these meet a design aesthetic for the ladies! I play them in the rotation and they are a good set. The cue ball is not a favorite. I ordinarily replace it with an Aramith Measle ball.
Elephant Traditional - These were on clearance for $30 so I bought them. They are worth $30.00. Suitable for use in a pool hall or maybe some arts and crafts.
Vigma Stars & Stripes - If you have never seen this set in person, you are not allowed to comment. They are really stunning. I play them every summer in July and my friends who are either current or former military think this is the best thing they have ever seen on a pool table! Vigma balls play great and really stay clean.
Dynasphere Tungsten - sort of like the Elephant Beautiful set in that the ladies all say "Oh wow! Those are really beautiful!" It's always nice when the ladies say that.

for $50.00 they play great and are very high quality. Again, they are just in the rotation every few weeks for a few days.
29 Ball Color Set - Rare and hard to find. They play "ok" but are far from the quality of anything else I own. Still, I play them often because there are just so many different color combinations. Red / Pink for valentines, Green / Red for Christmas, Yellow/ Green for St Patricks, Black / Orange for Haloween, and so many more. I have at least seven of Red, Blue, Yellow, Green, Brown, Pink, and Black. The cue ball has a cool eagle on it. Again, these are fine for home play for fun.
I own several other novelty sets for specific games, but that is a different discussion.
Bottom line, I just enjoy variety. I eat a variety of foods, have several different cars, have a lot of different cloths and shoes, and I like all of them. I'm surprised by how passionately some folks are about their love or disgust over just a set of pool balls! Just have fun.