I have some kites I tried 25m lines on and ended up changing them back to 20m. I have some other kites that I really like on 25m lines.

The 3.5m HQ Alpha is one that I thought 25m lines would really wake that kite up. But they didn't. Back on 20's it is. My 3.3 Sting is one I'm wanting to try 25's on.

My 4.4m and 5.5m Reactors I really like on 25's and my 9m JOJO; 25's are a must with it. Also my 3, 4, and 5 Flux I like them on 25's.

My 5m Octane is another I tried 25's on and even 30's but I like that series of kites on 20's.

What are some kites that you have that you have a preference for what length lines are on it?

The major kite company's sell the kite a specific length line set because that kite was designed that way.
As you get into the race kites they come for the most part KO which means they are able to fly with most line sets the pilot desires. For the most part all kites are designed for 20m to 30m linesets, anything outside of that will change the flight characteristics of the kite unless the pilot alters the bridle. Altering the bridle is something the average flyer has no clue about. Not to say it can't be done, but those that race or have a quiver of the same kite knows what's going on and they tweek the kite to fit their style of flying.
Depending on space, abilities, and need the lines sets get shorter or longer. Other than what the kite was originally sold with I would say stick with what came with the kite or not.

As for the JoJo's a bit of AOA adjustment and they are killer kites on 15m to 17m linesets. Great kites by the way.