I know the treaty was very Dominion-sided, but the Empire gain anything at all from it? Aside from buying time to rebuild its forces. All I can seem to find on the subject is the bits on talos worship, hammerfell, and the blades.

nope. Now you know why practically everyone hates it.

http://www.uesp.net/wiki/Lore:The_Great_War_(book)

The terms were harsh, but Titus II believed that it was necessary to secure peace and give the Empire a chance to regain its strength. The two most controversial terms of the Concordat were the banning of the worship of Talos and the cession of a large section of southern Hammerfell (most of what was already occupied by Aldmeri forces). Critics have pointed out that the Concordat is almost identical to the ultimatum the Emperor rejected five years earlier. However, there is a great difference between agreeing to such terms under the mere threat of war, and agreeing to them at the end of a long and destructive war. No part of the Empire would have accepted these terms in 4E 171, dictated by the Thalmor at swords-point. Titus II would have faced civil war. By 4E 175, most of the Empire welcomed peace at almost any price.

it was only a "treaty" in name..

Empire gave up Talos Worship, southern Hammerfell, and dissolved the Blades (the Thalmor saw the Blades as a threat)...

the Dominion gave up nothing we know of....


So in all reality, it wasn't a treaty, it was much more of a "terms of surrender"