[pshirali]

OT: If you feel things are really getting complex already, do ponder over whether there is scope for you to simplify things. Simplifying architecture is IMO more valuable than representing complex architecture, even if it is done using the best available tool.

UML helps. Recording design decisions and how classes are meant to be called/used is generally good reference for a rainy day in the future.

Since you are using Python, ensure you sufficiently document classes' purpose/responsibility in docstrings. Ensure the most important pieces of info stay close to the code where they are implemented.