Great to hear! It definitely must be difficult to balance having a clean, easy-to-use interface with lots of powerful features.
I’m happy to do my own custom work where it falls outside of what is reasonable for you to include for the average user – especially with regards to things that need packages installed on the server, like Tika and spaCy. But its good that you’ll be adding support for Tika, since it is a pretty “Core” feature that is supported by various competitors. Adding this support through an add-on system seems appropriate to reduce bloat in the core plugin for those who don’t need the features – it is what many other plugins do (SearchWP is a good example). The add-on system should also open the door for further integrations/extensions by other plugins/users.
I’m glad that I could be helpful and I look forward to seeing what you come up with!