The Center is integral for a few reasons.
1. He's the first person to touch the ball every play. Getting the ball cleanly to the QB is an art, one must be able to hike the ball, fire off, or pass set all in one motion. It's much more difficult that it looks. Shot gun snaps even more so.
2. Center is the signal caller for the line, most offenses require the center to make pass protection calls, and some ask him to make adjustments in run blocking.
3. Center is usually 1 on 1 with a NT or Middle backer, has to be athletic AND extremely physical to keep the heart of the line from collapse.
A Center who struggles delivering the ball, making the appropriate line calls, and has difficulty handling physical NT's and aggressive MLB's will cause ripples through the offense rendering it ineffective.
The football ignorance from some on this board is astounding....