Well, it's a marginal improvement. Nothing to really write home about, though.
My first D&D character was a fighter and it's remained my favorite class. However, I've been distinctly disappointed by 5e's fighter. It's boring and it's compounded by the fact that the core rules don't even have any of the combat maneuvers (aside from grappling and shoving) that were present in 2e and 3e/3.5e (and, I assume, 4e—I didn't play that edition).
Weapon Mastery is nice. It's a callback to BECMI/RC. But I don't see the need to have any more Masteries beyond the initial 3 (especially when you can swap them out on a long rest). That leaves feats (again) as the defining feature of the class. Problem is, though, there are no fighter-only feats, nor are there any higher-level (8th-, 12th-, 15th-, 16th- and 19th-level), more powerful feats (so you're fated to pick the also-ran feats that you didn't want at the earlier levels). The shame is that there's tons of inspiration to be found for potential higher-level feats (or other features) in 3.5e's Tome of Battle and in 4e's fighter exploits.
Adding Persuasion to the skill list is nice, but it's literally the least that they could have done to give the fighter something non-combat related (and with Charisma not being at the top of a fighter's Ability Score priorities, it's not that great).
Also, the Champion remains boring.