Armature Rigging Modules is a Blender add-on that provides modular rigging for almost any armature. Rigs can be as simple or as complex as you need, and are set up in a fraction of the time the manual process takes. The add-on includes scripted mechanics such as soft IK and automatic IK/FK switching, and supports arms, legs, feet, hands, spines and heads.
This is a tool for rigging existing armatures; it does not do any weight painting. It is a free project, so dedicated individual help is not guaranteed unless you support the developer financially. The add-on is part of the developer's B.L.E.N.D add-on collection and is also included in Mr Mannequins Tools.
The developer notes this is a favorite project that has already saved hundreds of hours, with many updates, further additions and future development planned. Support can be found in the B.L.E.N.D category of the developer's Discord server as well as in the GitHub issues. A demo video is available, and the developer recommends viewing it in 2K or 4K.