If Smith, DJ, and Hali are all gone next season, wouldn't the Chiefs have the cap room to keep their other players?
Here's a list of promising talents that will come up for free agency before 2020: Bennie Logan, Dee Ford, Marcus Peters, Mitch Morse, Chris Jones, and Tyreek Hill. This is before you start counting guys from the 2015 and 2016 draft classes that may start playing an important role this year: Chris Conley, Steven Nelson, Ramik Wilson, and Parker Ehinger. If Smith, Johnson, and Hali do come off the books next year, that alone will open up $32 million under the salary cap ceiling, not a small number, but that will go quickly as Logan, Ford, Peters, Morse, Conley, Nelson, and Wilson all come up eligible for extension. What corners will have to be cut so that the Chiefs can stretch out $32 million for a high-end nose tackle, a solid edge-rushing linebacker, a premiere cornerback, a quality center, a decent possession receiver, a good nickle corner, and the middle linebacker to complement Derrick Johnson's replacement. And the second year of these extensions will certainly eat into the cap space for guys like Chris Jones and Tyreek Hill.
For the lack of a first-round pick, none of these guys approaching extension eligibility and/or free agency are likely to be replaced by a player to be drafted in 2018. The Chiefs said 'no' to some of these guys when they said 'yes' to Eric Berry, and now the Chiefs will be forced to release players that are making a difference now while Berry is sidelined with an injury that will likely prevent him from ever again playing like the Berry we've known.
No, the Chiefs will not be able to keep everyone just because they're opening up approximately $32 million in cap space. And half of that is subject to whether or not Smith actually departs this year, which won't likely happen if Mahomes is deemed to have not made enough progress in Reid's system.