I very much like Nextcloud too, and have set up/administrated three instances in various contexts (family, friends, work).

It has a lot of great features and good multi-platform support. I also like that the company is based in Germany, and I had good experiences contributing to their code.

However, I do have to say that the software is somewhat clunky and slow, and the clients can be a little rough around the edges. (The desktop client has a particularly nasty bug that likes to clobber git repos.)

So if ownCloud comes out of the rewrite as sleek and reliable as they claim, they would be worth taking another look at. Until then, I'll stick with my Nextcloud...