Marlin safety features:
Self draining cockpit with large freeing ports which let water out but not in.
3 electric and 1 manual bilge pump. Low level float switch with option to pump out automatically. For use when boat left unattended - high level float switch to keep bilge water level low. Also spare electric and manual bilge pumps.
8 man liferaft in cannister. 2 life-rings, with line and floating light.
Fixed, fold-down, boarding ladder.
Additional "sheath" on bow and keel - to protect from collision with debris, or grounding on stones.
Spare VHF with separate aerial.
Radar reflector.
Personal locator beacon.
Radar and chart plotter with AIS receiver that overlays AIS positions.
Second chart plotter and second sonar.
Separate "starting" and "service" battery banks - each 100 Ah at 24 volts.
Spare starter motor and spare alternator for engine. Spare impellors, fuel filters,...
Drain cock on fuel tank - so any water can be removed.
Emergency tiller for use if hydraulic steering fails.
3 main anchors (each with chain and warp) - Danforth; Manson and Fortress. Sea anchor (drogue). Also "lunch anchor".
All Mitchells have a "weed box" which allows access to the propeller to clear rope from it, from inside the boat.
LPG and Carbon Monoxide alarms (though I now use electric cooking myself)
4 fire extinquishers and a fire blanket.
Flaps to cut off air access to engine in case of a fire. Also port to allow fire extinguisher to be directed into engine.