I think it's hinted that he found someone else. He ended up not being the last of his kind in the end. Of course, that's not explicitly said, but that makes the most sense to me.

Honestly, it's been so long since I've played VII past the Midgar section that I don't remember much of my opinions on what should be changed. I didn't mind Cloud that much, but I didn't really like him either. I do enjoy Sephiroth to an extent (and I enjoy that he is present throughout the game and not just in the closing moments as the final boss). However, I also agree the the Jenova/Sephiroth story line seemed a bit convoluted based on my memory of it.