Kuni places mid on most tier lists by Korean and Japanese players. Her pokes, punishers and the general risk/reward ratio of her moves just isn't good and she has nothing that is "stupid good" IMO. She has no greater reward that comes from mastering her as a character either as is the case with for example, Nina's instant ws1 combos, Lee's b2-mist step combos, Jin's parry, Mishimas in general, or instant while running moves with like Drag's wr2 or King/AK running 2+4 or giant swing. Even Paul, who is a simple character as well as Kuni has just frame demo man and his qcf1 combos do a shitload of dmg. He is risky as well as Kuni, but he has very good punishers and higher dmg output.
Anyways, here are some tier lists. I will say that Bruce is the best character to pick up initially, easily top 5. He has no just frame inputs and the only thing that is hard to do with him is the dash d3,4 after a ws2,1 launch. He has absolutely everything you could want from a character, he is easy to pick up and learn, yet he still has loads of depth and dirt that will actually work and win you matches. Even against people who know the match-up he is still an absolute beast. I mean Knee is an amazing Tekken player, but his Bruce is very basic and all he did was a couple of well placed b2's to completely blow up Bronson Tran at EVO grand finals this year.
http://www.tekkenzaibatsu.com/forums/showthread.php?threadid=127189
http://www.eventhubs.com/images/2013/jul/09/tekken-tag-tournament-2-tier-list-nobi-and-shudy/