I'm using LXDE (Lightweight X11 Desktop Environment) on my laptop. First of all, it seems to be a resurrection of the long dead Unix philosophy: simple tools that do specific things well. Second of all, it makes no sense to use Mint on a laptop until Mint makes whole-disk encryption easier. It's a piece of cake in Lubuntu.
LXDE seems to be missing some very basic things, but it also does some very basic things right. In Mint, there are no themes (okay, maybe if I wanted to spend my life looking through themes designed for 12-year-olds) that provide significant contrast between the window with focus and the other windows. LXDE does this in an attractive fashion. It has panels, rather than the brain-damaged crap the Gnome project is trying to foist on people.
Why am I more willing to spend time adding functionality to LXDE than to figure out how to customize, say, Mate? Mate is a very heavy-weight environment. Overall Mate is well thought-out and well-implemented, and it is available for more secure environments than Mint, but it is yet another attempt to make Linux into a Windows clone.
With a new Mate installation, I have to spend hours uninstall useless crap, disabling useless background daemons, etc. LXDE saves this hassle--I have a machine I can halfway trust before pounding on it for a week.
LXDE is a better idea than Mate, and a much, much better idea than Gnome Shell. It's worth spending time on. Or so I think so far.