Gentlemen <salute>
In order to describe someone as "overrated", we should have an idea of how they rate in the first place. Just to throw a few names out there I browsed a few different sites which listed the worst (and on one site the best and worst):
One site names the 10 best of each army:
1) Nathan B. Forrest 1) Ulysses S. Grant
2) Robert E. Lee 2) Benjamin H. Grierson
3) Patrick R. Cleburne 3) George H. Thomas
4) "Stonewall" Jackson 4) William T. Sherman
5) James Longstreet 5) Winfield S. Hancock
6) A.P. Hill 6) John A. Logan
7) J.E.B. Stuart 7) Quincy Gilmore

John B. Hood (1862-1863) 8) Andrew A. Humphreys
9) D.H. Hill 9) James B. McPherson
10) William J. Hardee 10) John M. Schofield
The 10 worst from the same site:
1) W.H.C. Whiting 1) Egbert B. Brown
2) John B. Hood (1864) 2) John Pope
3) David E. Twiggs 3) Samuel Heintzelman
4) Benjamin Huger 4) John C. Fremont
5) William H. Carroll 5) George B. McClellan
6) Braxton Bragg 6) Benjamin F. Butler
7) John B. Floyd 7) Louis Blenker

Gideon Pillow 8) David Hunter
9) P.G.T. Beauregard 9) William Rosecrans
10) Theophilus Holmes 10) Ambrose E. Burnside
On another couple of sites there were lists of the worst combined:
1) Benjamin Franklin Butler (US)
2) George Brinton McClellan (US)
3) Ambrose Everett Burnside (US)
4) Braxton Bragg (CSA)
5) Franz Sigel (US)
6) Nathaniel Prentiss Banks (US)
7) Gideon Pillow (CSA)

Don Carlos Buell (US)
9) William S. Rosecrans (US)
10) Hugh Judson Kilpatrick (US)
1) Gideon Pillow (CSA)
2) Benjamin Butler (US)
3) John A. McClernand (US)
4) George McClellan (US)
5) Braxton Bragg (CSA)
6) Ambrose Burnside (US)
7) John Bell Hood (CSA)

Don Carlos Buell (US)
9) William Rosecrans (US)
The names offered so far include Robert E. Lee, Albert S. Johnson, John Bell Hood, Braxton Bragg, and John C. Fremont.
Robert E. Lee makes the "best" list.
John Bell Hood makes both the "best" and "worst" on one, and "worst" on another.
Albert S. Johnson makes none of the lists.
John C. Fremont makes the "worst" on one list.
Braxton Bragg makes the "worst" on all three lists, so it's hard to imagine him as overrated.
Anyone else of the 10 best you would consider overrated?