I think it's fine to leave the profile as the default behavior, but change it a little bit so that install_dir is empty unless specified, in which case you would reverse the logic:

```python
if pargs.install_dir:
    # explicit install_dir overrides profile
    dest = pargs.install_dir
else:
    # this is normal / default
    dest = dest_for_profile(...)
```

and probably update a docstring or two to match.