Xfce4-panel can use Gnome panel applets if you install the package xfce4-xfapplet-plugin. Not all applets will make as much sense though. The session applet, for instance, will attempt to log you out of Gnome 2, which isn't running, so it will do nothing. The same goes for applets that handle the screensaver and other such DE-specific things. In those cases, the xfce4-panel will have its own plugins that provides these features.
App-indicators are based on DBus, which means they can be used on any desktop environment that supports it. This is one of the big benefits of indicators. They'll work well on KDE, Gnome Shell, Unity, LXDE, Xfce or any other environment. I do believe that there is a native xfce4 plugin to display indicators, but in any case, you'll be able to use the Gnome panel applet just as you did in Gnome.
Using a custom dock like Docky or AWN, should not be a problem at all. I haven't tried it.
I see no reason why you shouldn't be able to use Compiz and all its plugins. I haven't tried that either. But I have used Xfce4-panel with Compiz, and that works well.
You can use the same icons, but window decorators will be different. Perhaps if you use Compiz, you can still use the other themes, but I don't know.
You can just install xubuntu-desktop, except for a single conflict: the notification system. You'll be told that ubuntu-desktop needs to be uninstalled, but that will not uninstall all your software. However, since both Gnome and Xfce provides tools to handle screensavers, sessions, etc, it might be cleaner to do a fresh install.
What seems to have happened is that XFCE have changed some settings on your system, as such, your Ubuntu looks the way it does. You're going to have to reset some of these settings back to their defaults by running a few commands.
Reset Icons
gsettings set org.gnome.desktop.interface icon-theme 'ubuntu-mono-dark'
Reset Theme
gsettings set org.gnome.desktop.interface gtk-theme 'Ambiance'
gsettings set org.gnome.desktop.wm.preferences theme 'Ambiance'
Reset Login Screen
sudo dpkg-reconfigure lightdm
The above will fix the looks of the unity. Next is the login screen.
Reset Login Screen
There are two options for this:
First:
Run these commands:
sudo update-alternatives --config default.plymouth
Then choose your ubuntu option: /lib/plymouth/themes/ubuntu-logo/ubuntu-logo.plymouth
And then run: sudo update-initramfs -u
Second:
Run in terminal:
sudo dpkg-reconfigure lightdm
After running the second (or even the first option) you will probably NOT see the results just yet. As those scripts are not updating all necessary files, edit the lightdm.config
file (thanks to help of this post https://askubuntu.com/a/421322/223469):
sudo gedit /etc/lightdm/lightdm.conf
And change values to (previous value was probably xubuntu):
user-session=ubuntu
greeter-session=unity-greeter
Save and reset.
After those changes the login screen should appear.
All what is left to do is to return loading screen, but so far I haven't managed to do that, but will update once I find the solution
Best Answer
It all depends on how you want your system If you just want bare xfce as your desktop and run all the applications you have been running. You can just do
apt-get install --no-install-recommends xubuntu-desktop
and remove those unity and gnome related desktop packages using synaptic and choose xubuntu session from gdm during login. Adding to what
jpfluery
pointed out the given script tends to replace applications such aslibreoffice, evolution, totem, empathy, banshee, gedit
with some lighter alternatves i.eabiword,gnumeric, thunderbird,parole,pidgin,gmusicbrowser,mousepad
etc which are recommended packages of xubuntu. With xubuntu what you will get isIf you need xubuntu-artworks, plymouth theme and even gdm theme you can install them as well.