Right now, during the (open)SUSE installation process, the changes to be performed on the storage devices are presented as a list of actions such as:

• Resize ntfs partition /dev/sda1 by 100 GiB
• Create partition /dev/sda2 (15 GiB) for / with btrfs
• Create partition /dev/sda3 (85 GiB) for /home with xfs

That is, something like this screen.

An openSUSE user suggested the idea of having in the same screen a tab with a graphical alternative, using a before&after approach to represent the initial layout of the disks and the proposed one. Here is the bugzilla entry including mockups.

Technically it should be possible, so it's worth a try.