Compressing all the .exe, .dll, and .pyd files with UPX would reduces the hard drive footprint by 10MB. This should also have a size reduction on the installer exe.
Recommended compression lvel/type is "nrv2e" (LZMA compression could have some issues on some machines in our experience over at PortableApps)
Recommended UPX command line:
for /r %%e in (*.exe,*.dll,*.pyd) do upx.exe "%%e" --best --compress-icons=0 --nrv2e --crp-ms=999999
Or use the PortableApps.com AppCompactor: