

Timeshift is great for getting your system back after a major fuckup. But i dont think it works as a backup solution that can be transplanted to other systems, but i never tried.
I use Kup to backup my important stuff. It comes with a kcm that integrates into KDEs settings menu and can do automated timed backups. Its a wrapper for bup. It also does Incremental backups.
I dont know about Gnome, but kde plasma “should” run and be usable with 1GB ram. At least ive seen some posts about people doing it. I think at minimum you would need to customize your ram related kernel parameters like swappiness, the watermark scale factor (kernel memory threshold for caching) and stuff like that. But i cant say ive ever run such a small system with a DE.