A few notes about this stage! This is a good time to make a backup copy, right before you install a full fledge Desktop Environment. A dd copy is fine, or a compressed file based backup might be less than a gig. Also note that sound and a full xorg package can be installed here along with any firmwares you may want. If you install things like ssh and ncurses based cli utilities you have a full cli image ready for anything. Sound and full video modes, including a mouse, actually work without a desktop. "startx" can give you a full HD, true type adjustable font'ed' Xterm with a clickable mouse, cut-n-paste, and everything! Some full screen games can be fully functional from a base like this. Full screen HD ncurses can be a beautiful thing. Logon managers and desktop environments are extras! Becoming fluent at this level means if your DE lacks a gui for some task you won't get lost, you simply open a terminal!
As Sparty said, if you have a system with VM capability, build it there. You can import your bare metal image you from a backup later also. With the xorg installed on the CLI based image, you can have mouse and cut-n-paste function (vdagent?) between the VM host and this new system. If this is system #1, make the backup before all the extra gui parts are in place, and then once you have your xfce/vm system built, import that base image and use it to explore all other DE flavors in a VM! As this flow develops you can upgrade and test in the VM's, making your upgrade to the main system safer.