Castle wars isn't fun if you're not that good at it. There's nothing like outrunning a mage while wearing rune by just cadeing. The better you are, the more fun you have because you can pwn noobs. :)
The same goes for any minigame really. If you're a noob, you don't like Clan Wars as much because the whole point of it is killing while in Castle Wars, the goal is securing your flag and capturing the other team's flag.
Overall, it depends how good you are at something.
Clan Wars, there is nothing like good-old, classic fighting with a bunch of clanmates. ^.^ Besides, we barely get a chance to play Clan Wars anyways, but Castle Wars is basically something we do when no one can think of an event.
To be honest they need to work on clan wars I hate that some parts are single combat and some are multi, castle wars is easier and not hard to figure out for me because I always win most of the time, almost 1k tickets just because I play it every day but
"Every gun that is made, every warship launched, every rocket fired, signifies in the final sense a theft from those who hunger and are not fed, those who are cold and are not clothed." Gernaerl/President Dwight D. Eisenhower