My Recommdations:
94':
Team USA (Heavy D!, Lucky, Brian) [It's their only apperance in the series (98' doesn't count).]
Team Mexico (Takuma, Ryo, Robert) [Could be in 98 instead]
Team Korea (Kim, Chang, Choi) [Could be in 98 instead]
95':
Women Fighters Team (Mai, Yuri, King)
Fatal Fury Team (Terry, Andy, Joe)- Both team makes since prior to 96'.
96':
Rival Team (Iori, Mature, Vice) [Explained why Iori is alone in 97']
97':
Hero Team (Kyo, Benimaru, Daimon) [Beat Orochi with Kyo and then win against Iori.]
98': There are other teams, but I recommend to use these.
'97 Special Team: Billy Kane, Yamazaki, Blue Mary
Oyaji Team: Heidern, Takuma, Saishu
Special Teams:
Superstar Team: Terry, Kyo, Ryo
Sidekick Team: Benimaru, Robert, Andy
Rapid Button Team: Billy Kane, Joe, Chang
Flame Team: Kyo, Chris, Saishu
Cap Team: Clark, Lucky, Terry
Headband Team: Joe, Yuri, Daimon
Weirdo Team: Robert, Choi, Kensou
Baseball Team: Ralf, Mary, Lucky
Damage Team: Ralf, Brian, Chang
99':
Ikari Team (Ralf, Clark, Leona, Whip) [win with 280+ Points to battle Kyo]
2000:
Special Team (Kyo, Iori,K'+,Whip+) [Fought with Kula] [+ means optional]
2001:
Hero Team (K', Maxima, Whip, Lin) [Best Ending prior to the NESTS saga]
2002: Any Unused Team/Characters up to this point.
2003:
Special Team- 3 Sacred Treasures Team (Kyo, Iori, Chizuru)
XI:
Hero Team (Oswald, Shen Woo, Ash)
Kusanagi & Yagami Team (Kyo, Iori, Shingo)