There is a good case for changing the name of the python-simpletal package to python-SimpleTAL, but all of the above packages are named based on the actual python module name (i.e. the name you would import in python to access the module), rather than strictly following the upstream source name.
Both Durus and TPG provide executables along with the python modules; in the Durus case, there is a decent argument for putting that into a separate package.