As you said thay you have descent knowledge on CV, IMO you may want to focus on GAN based models. Although, GAN itself is very vast field but i can suggest you one topic that i myself thought in my final year.
You may have heard of StyleGAN which produces very high res images of persons that doesn’t exist.
You can focus on creating faces between interpolation space of two images. There can be infinite numbers or faces generated by using linear interpolation of two face vectors. You could start with two and then expand it to work with even multiple face vectors in which the interaction of vectors may become little bit complex.