So I was thinking, we can create knew subclasses, which is cool and everything. However, do you think the great developers at dnd beyond will eventually let us create our own classes. Not subclasses, but actual full blown classes, with there own subclasses. Would anyone else use that feature?

If you search the forums, you will find several threads asking this question.  The developers have essentially said there are no plans to do so at the moment.  Classes are a lot more open ended that subclasses, and require a significantly greater level of complexity: it's highly unlikely that the developers could envision all the kinds of new systems and mechanics that would need to be possible to allow for new classes.  They also have a lot of other features planned that they believe will benefit more users than full homebrew classes will, so those get a higher priority.  It's not impossible that they will add it eventually, and they do pay attention to feature requests, but it's not currently on the roadmap.