The Ortiz comments aren't really accurate. First, no hitter is making $30 million a year and almost no one is making $25. The best position players are making $20-$25, not $25-$30. Second, and more important, Ortiz is not as good as the guys making that type of money. Or, at the very least, he is not as good as the teams expected those players to be when they signed them to those contracts.
On a rate stat level, Ortiz' performance last year was most comparable to that of Choo. (They have a wRC+ one point apart and wOBA's with .010 although Choo gets there with less power and more OBP.) Choo signed for $18.6 million this offseason. And, while his terrible defense makes him basically the equivalent of a DH, he played in 17 more games and accumulate 112 more PA, making his fWAR 1.4 higher than that of Ortiz.
If we are looking for a value comp, we need look no further than the Red Sox 1B. Napoli's overall value last season was virtually identical to that of Ortiz at 3.9 fWAR to Ortiz' 3.8. His health concerns probably mitigate substantially against the age difference. He signed a contract that was pretty much the same as the one Ortiz got a year ago.
Basically, the contract Ortiz is on, which he signed as a FA, is equivalent to his fair market value, more or less. Part of signing a contract is giving up the right to renegotiate terms every year. If Ortiz wants to sign an extension which builds in a discount for the Red Sox to guarantee him money in 2015 a year before they need to, I would be fine with that. I would not offer him a FA-rate extension a year in advance though. It sets a terrible precedent for future dealings with players to do so.
If Ortiz has another great year, a 2-year, $30-34 million dollar deal is probably waiting for him after next year. If he struggles or gets hurt, he might be looking at a 1 year, $5 million dollar deal with incentives or even just be out of baseball entirely. If he wants to sign an extension for around $10-$12 million right now, I'd do it. I'd also consider a $15-$16 million dollar extension with a team option at the same rate added on for the third year and no, or minimal, buyout. If he is looking for $15+ million without the team really getting anything, I try to politely explain to him that I'm not saying no because I don't think he's worth it but because the team has to hold the line on not being willing to extend players who are currently under contract unless they are willing to take a discount. $15 million for Ortiz, as evidenced by his last contract and the contract Napoli just signed, is not a discount, or if it is, it is a very slight one.
The short version of all of this is that it is bad for business to extend players unless you get a discount. Extending Ortiz should only happen if he is willing to take a discount, either in dollar terms or by giving the team options at the end. And, in either case, he really should keep his contract complaints between himself, his agent, and the front office rather than discussing it in the press.