I will augment your responses here with an answer to the question you didn't ask.
Why a player SHOULD NOT join a clan?
B/c you expect it to instantly 'make your better.'
B/c you are a negative drain on the community, problem causer, going to give the clan a bad reputation and possibly even force them to kick you from the clan.
B/c you don't actually like talking to people.
B/c you're not an active player - most clans have activity requirements, so if you go inactive for 2-3 weeks, you could get kicked anyhow. Also if you're not active but join CW, you take up a player slot that can't be reused by anyone until the next season.
B/c none of the benefits listed here appeal to you.
That said ... try it out. You can always leave if you don't like it. Just pick one and try it. TLA or TBA seem to be the best generic choices, meaning clans that appeal to many, not something specific targeting elite players or some other theme.