Evans is a good 4th line center and as @The Chicoutimi Cucumber pointed out, but is he a 3rd line center on a good team? I think he’s a passable 3rd line center when an injury occurs, but not someone you’d sign for that role specifically. I also believe he wouldn’t get as much icetime on a better team.
I’m not sure spending $2.5m on a 4th line center is good cap management. Especially if/when someone like Beck, Mesar or Kapanen breaks in the league, chances are they will be leapfrogging Evans in the lineup because you don’t want them playing 4th line minutes.