Sequel paths - like Giantess, Hyper Expansion, etc. are planned, but will not be implemented soon since they are more late game content
Muscle path is planned and already went to vote (but Milk won).
Pregnant is a maybe. I like the idea of Mia pregnant- but I don't like the idea of having to deal with the actual baby, so I still don't know if I'll add that one.
Various monster girls are also on my list.
It's very strange! As for me, the milky path and the pregnancy path are very much connected, because well... pregnancy = breast lactation. As for the pregnancy itself... well, there's a rollback function, isn't there? So, the baby will essentially roll back as if it never happened. Alternatively, the pregnancy could be a mini-finale, with a picture and text about the happy life of the hero and his girlfriend, followed by a rollback button.