In theory you can create an Anahita project which will use Anahita as one of the vendors. Then inside the project's packages directory you can put your own custom components and rewrite the composer so it would symlink to your components rather than what Anahita provides by default. Again haven't had a chance to try it myself yet, but it should work. If you got results, please take sometime and publish a page about it here. Others could really benefit from it as well.
I will try it and let you know if it works. I thought I could overwrite any core's file just by putting the new one under my packages components hierarchy. I wouldn't know how to rewrite the composer as you advice.
I made it work by copying the entire com_actors #component from #Anahita vendor to my custom component and changing the files I need to change, but I feel that's not the best way to do it, cause I lose the updates to it.