You're right that ChatGPT alone isn't enough for pronunciation, it's basically a written tool at the end of the day. What I see with my patients who are learning languages is they tend to neglect the phonetic side and it's a shame because you work that like a muscle, literally. If you really want to make progress on that, you gotta combine it with something like Speechling or Forvo to listen to native speakers say the words, and ideally you record your own voice to compare yourself. ChatGPT can give you context or explain grammar to you, but for pronunciation you need real audio feedback.
What intrigues me about your approach is that you get your texts corrected. That's useful but it's pretty passive as a process. In my opinion, what works better is when you create content yourself on subjects you're actually interested in. I've been reading a ton in English for years now, mostly gardening and physio articles, and that's how I pick up the terminology. ChatGPT can help you write posts about your passions and fix stuff, but it's gotta come from you, not just be an exercise. And honestly, finding a conversation exchange partner, even online, it's incomparable for actually practicing. Bots are cool for getting the basics down but a real person is gonna ask you questions you didn't think of.