Do not exceed the amps rating of the socket for more than a few peak seconds
no matter the ampacity of the plug or adapter you jerry rig.
Best approach would be to use Anderson PowerPole as a standard, for almost all power connections
use those to bring max power output from the unit, and then use a well made buss bar or splitter pigtail to support input to your devices.
Standard ciggie sockets are IMO a dangerous abortion, avoid like the plague for anything important, or that you use regularly. Never more than 5-6A and only for short periods, as in a few minutes. Even then they are risky, an inherently poor design!
Blue Sea has a nice socket design that twist-locks with the matching plug, but will also accept standard ciggie plugs for smaller (
Also the BMW/ Hella/ Merit/ Powerlet "Euro-style DIN" (ISO 4165) style is very robust.
Buy or make adapters for guests, temporary use of devices with standard ciggie plugs.