I have some ideas about sub-quarks and sub-leptons and the structure of them. I can't ask this question on the PhysicsStackExchange place because the only questions you can ask there are about mainstream-physics. Can I ask them anywhere, or just talk about it in a cozy chatroom, with a cup of tea? I couldn't find a tag so I put on the discussion-tag.
I have some ideas about sub-quarks and sub-leptons and the structure of them.
Stack Exchange sites are not places to share ideas. I generally wouldn't read too much into your word choice, but the fact that you say "ideas" instead of "questions" does suggest that Stack Exchange is not the place for the kind of post you may want to make, regardless of whether the topic is within the scope of any SE site.
That being said, I don't believe there is any site where non-mainstream physics is on topic. But I can't officially speak for other sites.
It would be fine to bring up your ideas in chat, just make sure that you're not too pushy. In the long run you may be best off finding another site outside the SE network that is oriented more toward sharing non-mainstream ideas.