I guess both gnome3 and xfce uses systemd for suspend and hibernation. So in general there should be no difference.
hybrid-sleep works not for me, neither hibernation, but i deactivated at the BIOS anyway. Suspend works.
I would have a look at the logs and see where it hangs.
Try this on both installations:
systemctl suspend
and
systemctl hibernate
Then after wake up, or hard reset, have a look at the logs:
journalctl --since=-30m | grep -A9999 "Starting Suspend\.\.\." | grep "kernel:\|systemd\[\|audit\[\|systemd-sleep\["
and
journalctl --since=-30m | grep -A9999 "Starting Hibernate\.\.\." | grep "kernel:\|systemd\[\|audit\[\|systemd-sleep\["