Yes, lets look at these players.
Boyle: 2x2.75m for someone who's better suited as a #4C.
Mojo: Not even listed as a center and has averaged less than 1 FO a game over the last two years. Makes 2x4.58m and belonged to one of our biggest rivals.
Seems like an excellent candidate to fill the hole we have.
Schenn: At least he's listed as a center... even if he's never played as one. Has averaged less than 2 FOs a game over the last two years. Makes 3x5.125m and belonged to our other biggest rival. Oh, and he was also moved for a pair of 1sts.
Another great candidate to fill our #3C hole.
So far you're doing great... lets keep going.
Stepan: At least he's a true center - which is saying more then most of your list. He was moved for the #7th pick and a high offensive D prospect and has a 4x6.5m contract. Oh and if WSH and PHI are our two biggest rivals, the Rangers would probably be #3.... And yeah guess what... they used to own Stepan.
An ideal option... assuming A) we had the assets to send to NYR, B) they would trade him to us and C) there wasn't a salary cap. Unfortunately this isn't fantasy land.
Eberle: Well he is listed as a center... so I guess that's something. But considering he's never actually played it and has averaged 1 FO every 10 games over the last 2 years... whether he was available, an option or whatnot is pretty irrelevant. And that's even before the fact that he comes with a 6m cap hit that we would be hard pressed to accommodate.
However after his amazing playoffs and his obvious fit would make him one of the better options we could get... how have we not discussed him previously.
Which leaves us with Hanzel, Bonino and Thornton. Big Joe signed an 8m deal - so it's probably pretty safe that we can scratch him off the list. Hanzel would have been a great pickup and that contract is pretty damn good (3x4.75m). He went to Dallas, and there's no guarantee that he would have signed here, even if we could have afforded him. Again, it takes two to come to an agreement, and at least in Dallas there's no guarantee that he won't see a top 6 role (Spezza apparently plays some RW).
So out of 7 names, we're basically left with 1 - Bonino. We've discussed him to death, so I'm not going back there.