The classes Point, Extent and Angle are so fundamental that it can be a nuisance having them in afw.geom with higher-level classes such transforms. Circular dependencies (such as
DM-10973) are easy to produce and difficult to deal with in Python.
I propose to move Angle, Point and Extent to a new sub-package of afw named afw.base.
Other names are certainly possible but I recommend something short, so C++ code can use the sub-package name unabbreviated, e.g. base::Angle.
At some point we hope to switch from the Angle in "afw" to the one in "sphgeom". This might be a good time to do that, but it will slow implementation because "sphgeom" seems to be missing some things we rely on, such as AngleUnits that allow code such as 90.0 * degrees and a few methods, such as wrapCtr and wrapNear.