Order of letters by frequency
etaoinsrhldcumfpgwybvkxjqz

K4 order of letters by frequency (- indicates similar frequency)
K, S-T-U, B-O-W, A-F-G-I, L-Q-R-Z, D-J-N-P, C-E-H-V-X, M-Y

So far…

NIE  ON N  O ITN   IIS          ETTN
OBKR UOXOGHULBSOLIFBBWFLRVQQPRNGKSSO

ASA T  TT E  S A E O   S   I  
TWTQSJQSSEKZZWATJKLUDIAWINFBNYP

 AA    ES  E  A     EO O O E  
VTTMZFPKWGDKZXTJCDIGKUHUAUEKCAR

-Kryptos Fan