Well, the jackets from Schuylkill, or otherwise produced by contractors to the Army pattern, were pretty sharp...
The Richmond jackets were rather plain in comparison... with wood buttons, and other quality control and standardization issues...
But we might grant that the Confederate "gray jacket" plain as it was served its purpose in camp and field.
Many Union soldiers felt constrained to yank the fancy tape off of their Army jackets, and retailor the collars to a more comfortable height...
Some Indiana Cavalrymen at Petersburg in 1864 with variously modified jackets as above...
Some Union Cavalrymen in Tennessee; only the chap at far left seems to yet have all the trim on his jacket...
The only practical advantage of the Army jackets over the more comfortable flannel fatigue sack, was they were made of the sturdy uniform kersey cloth, and perhaps to slightly more advantage in colder weather...
Some of the Northern States procured and issued to their volunteers cloth jackets with various branch trim, like the New York Jackets... as worn by these chaps of the 23rd New York...
Or slightly plainer, (without the colored trim) like the Illinois jackets...