based on overall W-L it is the Cincinnati Reds. I looked and here is why...

Player     RD/YR    W-L    ERA   K    WHIP   Level

HBailey   (1 2004)  3-1    2.27  27   1.13    AAA
PDumstrait(1 2000)  5-1    1.94  26   1.22    AAA

JAvery    (5 2005)  5-2    2.91  30   1.12     AA
TPelland  (9 2002)  1-3    4.08  34   1.50     AA
SLeCure   (4 2005)  4-0    3.09  33   1.72     AA
CVazquez  (4 2002)  3-3    3.05  33   1.29     AA

RGardner  (6 2003)  5-1    1.65  25   0.87     A+
JCueto    (FA2004)  2-3    3.53  37   1.48     A+
TPauley   (2 2003)  0-0    0.00   3   3.00     A+
Twood     (2 2005)  1-0    6.35  12   1.94     A+

SWatson   (2 2006)  3-1    2.09  56   0.98      A
RGonzalez (4 2004)  6-0    1.59  24   1.11      A
JSmith    (6 2006)  2-3    2.17  30   0.86      A
TWebb     (8 2006)  3-1    2.88  37   0.99      A
DThompson (8 2003)  5-0    0.96  24   0.64      A

Tyler Pellend has split time as a SP/RP (future closer?), Travis Wood was injured for the beginning of the year, and the long injured Thomas Pauley is back to pitching (a good sign). But what a turn around from a system of pitchers that appeared to be bust after bust aside from Bailey.