Attempting to make Clan Culture more interesting

Windclan are the most traditional and because Windstar didn’t like cats she didn’t know, it continued throughout clan history and they don’t accept outsiders into their clan.

Shadowclan are the closest with their clan mates but are most hostile to other clans.

Thunderclan has always felt like it’s their duty to help everyone. This partly stemmed from Thunderstar being very protective of his loved ones.

Riverclan holds competitions on who can eat the most prey once a moon as they pride themselves on looking fatter than the rest of the clans. They also pride themselves on looking well groomed and because of this, they’re mistaken for kittypets often.

Skyclan is the most adaptable clan and adapts to new environments such as moving from the gorge to the lake.

I have a feeling the Clan's issues started way back with Ripplestar (the one who planned a sneak attack on the Gathering) as, before him, the ShadowClan leaders and cats we saw were quite reasonable - the six month apprentice rule started from a ShadowClan queen, the leaders would occassionally make jibes at the other Clans, but were also concerned about other Clans and frequently discussed the neccessity of warning other Clans about dangers. In that way, I like what you saying about the spying element.

After Ripplestar, there were still a few good leader moments - Yellowstar seemed deeply concerned about the 'Clan leader's word is law' code - but we saw a gradual shift in ShadowClan behaving selfishly and claiming to be the biggest and most neccessary Clan. Therefore, I would say that their pride in providing information and protecting other Clans mutated into a very self-centered, egotistical Clan which easily bred incompetent leadership and a lack of care for mentoring and medicine.

And when they do do any of this, it’s only temporarily:

•In The Sight, they had a daylight gathering to lower tensions but something similar is never done again despite the unlimited reserves of hostility that these cats have had thereafter.
•In Bramblestar’s Storm, they had the memorial stick for those who died in the Dark Forest Battle but was washed away within eight chapters and no attempt was made to set up a replacement.

I've always saw that as being mainly a product of Firestar's leadership. In the original series Firestar's tendency to want to help everyone was controversial and led to him being ostracized, rather than just being a natural part of their culture. While Bluestar had some of the same traits, you never get the sense in the prequel that her whole Clan was just always like that (remember her Clan also produced Thistleclaw, who was her contemporary, and his violent and xenophobic tendencies, while frowned upon in his Clan, weren't considered so disqualifying that he wasn't considered almost as good a leader candidate as Bluestar!), and even then it wasn't to the same extent as Firestar; she did help WindClan when no one else did, and let in two kitty pets, but some of the other cases of ThunderClan helping out in the first series were Firestar acting on his own and getting into trouble with Bluestar for it later, and even then Bleustar's actions were controversial in her Clan.