Free agency in any sport that artificially depresses salaries for those players not yet eligible for free agency is always going to result in "overpriced" players, and players who reach free agency at a later age will tend to age more poorly than those who reach free agency at a younger age. This is just common sense. Since you can't easily acquire a superstar (drafting superstars is difficult, takes time, and other teams are in play in ways that you can't compete against - after all, if you don't pick first, you are at the mercy of other team's selections), when one is available, you will need to spend.
In the NHL, where (based on my limited experience) unrestricted free agents are pretty much limited to players in their late 20's at the youngest (save for players not considered good enough to have their RFA contracts renewed - I'm sure there are other exceptions), you are inevitably going to see many, many of those contracts wind up "overpriced." That's just baked into the cost of signing a free agent, so I don't think "overpriced" is an accurate description. If you sign a UFA, you should expect to get a few years of good performance and then a decline that you hope is graceful. A player who retains high value over the entire course of a contract is going to be so rare that such an outcome should be treated as a bonus, not an expectation.
You can choose not to play the top tier UFA game, but you're artificially limiting your options to cheaper UFAs, trades, and homegrown players. That can and does work, but sometimes the best option is to spend millions on a top quality player to round out your team. Just accept that you're going to wind up spending more money for performance than you would on a cheaper option (after all, if you had that cheaper option, you wouldn't be in the UFA market).
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