Designing visible steps into a presence fleet

Does a naval presence vessel need a particular level of firepower, or are its facilities more important?

Both matter, but the key is a visibly graduated hierarchy beginning with a modest sloop and rising through frigate, destroyer, and cruiser levels.

Graduated presence depends on both facilities and firepower because each arriving class must look meaningfully more capable than the last. Starting with an expensive, heavily armed frigate forces every higher warning step to become larger and costlier. A lightly armed sloop or offshore-patrol-vessel type belongs at the bottom, followed by a frigate, destroyer, and cruiser-level ship. The force structure makes escalation legible while reserving the most capable combatants for higher-risk signals.