Extra missile launchers depend on the ship's mission

Would a Kirov-derived design benefit from reloadable box launchers alongside VLS, or deck-mounted Naval Strike Missiles?

Only if the missiles serve a clear role within the ship's wider weapons, sensor, and support arrangements; the launcher choice needs that context.

Extra launchers need a useful missile and a clear role within the ship's overall weapons fit. Their value depends on the sensors available, the operations expected, and the support needed to sustain them. A launcher cannot be judged in isolation from those choices. Several options remain possible, but choosing a system requires a fuller design.