You could use LVM thin p for / and /home.

The advantage is LV sizes are virtual, and can be larger than the VG. So it's an on demand pool of extents, assigned when needed by whichever LV.

The installer won't let you over commit though. So what you do is create only / and set that volume size to a practical max. Post install create a new LV for /home and make it also a practical max size. The combined root and home can exceed the space in the VG.

The gotcha is if the actual combined used space in those two for systems exceeds the pool size. That'll break things.

But in the meantime it obviates filesystem resize. If you set to a practical max you won't need to grow an fs. And if you want to shrink, just use fstrim and unused extents will be returned to the pool. It's actually a lot more efficient and safe than fs resize.

Chris Murphy