I disagree, because it's a very public power that's liable to provoke an instant public reaction if it's used abusively. The most dangerous powers are arguably the ones that can be used subtly and behind the scenes.
If the President doesn't use the power wisely, we can vote him out.
And...how do we know whether or not he's using the power wisely?
But what good did it to the public to KNOW that Clinton pardoned people right before leaving office? If we can't hold the President accountable, knowing about it does us little good -- we can't fix it.
If we don't like Bush's NSA program, we simply vote someone into office who opposes it, and that new President will stop the program. But a new President can't 'unpardon' anybody.
Appointing judges is another huge power, but the Senate can stop that if the President picks a bad one. And if the President goes nuts, the military can even prevent him from making a complete mess out of a military operation.
So I stand by my personal opinion that the power to pardon, while as a practical matter not having been abused TOO badly, is the biggest unchecked power of the Presidency.