Any UML diagrams that I do draw tend to be sketches rather than comprehensive models. (Click on the image to enlarge it) ... software architecture diagrams should be grounded in reality too.

The C4 model consists of a hierarchical set of software architecture diagrams. These diagrams are both easy to create and easy to understand for multiple intended audiences. BT.

The excellent book by Hofmeister et al [6] defines a Software Architecture methodology which has been used as a basis of the ST formal System Software Architecture specification framework [1], [2] and ...

The Object Management Group, the organization that standardized the UML, has an initiative called Model-Driven Architecture (MDA) which intends to standardize many of the elements required for SoC.