Headless dedicated server or player-hosted sessions for a low-traffic Godot multiplayer game?

For a small Godot 4.x multiplayer game expected to run only a few concurrent sessions, two documented hosting models are on the table: a dedicated headless server export on a low-cost VPS, or letting one player's client host the session through the high-level multiplayer API.

The headless server export strips rendering, audio, and display subsystems, lowering the RAM and CPU a host needs, and the high-level multiplayer API is documented to behave the same in headless builds, so networking code should carry over. The trade-offs point in opposite directions:

• A dedicated headless build reduces host resource needs but requires gating display-dependent code paths and operating a deployed process.
• Player-hosted sessions eliminate the hosting bill but tie session availability to one player, and NAT traversal may require a relay service with its own pricing.

Godot's documentation describes both paths but gives no traffic threshold or cost break-even for choosing between them, and server export presets differ between 3.x and 4.x.

At roughly what session volume does a minimal headless VPS become cheaper and more dependable than relay costs for player-hosted games? Which kinds of scene code most often depend on the rendering server and need gating in a headless build? Is the added deployment work justified for a hobby-scale title, or is player-hosting the pragmatic default?