Quoting acohen36 (acohen36@SDF.ORG):
I think Andrew mentioned Linux Mint 18.2 64-bit instead of Lubuntu (with the latter's LXDE) above. FWIW, a cursory review of the site linuxmint.com/release.php?id=29 doesn't yet show an available LXDE version of Linux Mint 18.2, although it _does_ show the "light" Xfce version of the same.
There's a... complication that hit LXDE, that all distros that ship it have been lately contending with. Along with XFCE, it's been built atop the gtk2+ graphics toolkit. But gtk2+ has now been supplanted by gtk3+, which has problematic aspects including breaking all themes and, frankly, a bad attitude towards everyone except GNOME. So, the LXDE people reassessed their roadmap and eventually reached the conclusion, a couple of years back[1], that continuing to rely on gtk would be unwise. They formed an alliance with a separate DE called Razor-Qt and created a joint successor project called LXQt that relies on the Qt5 graphics toolkit. Last I heard, some people who'd used LXQt had considered it still a bit unpolished, though I have no personal experience.
Anyway, this has left distros shipping LXDE in a short-term dilemma: They can continue to ship LXDE, but it's unmaintained upstream, for all practical purposes EOLed. Or they can jump to LXQt.
Going sideways to XFCE is something you and many others perceive as a good alternative. I find it likeable enough, but actually (when I last installed something with it) found it every bit as heavy-weight as GNOME2, which IMO is unacceptably wasting of RAM and CPU for its alleged advantages. (Typically GNOME3 implementations have of course been worse.)
This is one of the reasons I tend to say: LXDE is nice, LXQt is reportedly becoming nice (might be fine by now), and Moksha Desktop on Bodhi Linux is very nice, too.
In my own _personal_ view, XFCE is too heavy-weight, and all versions of GNOME3 are both too heavy-weight and buggy. Others obviously either aren't bothered by that or somehow have a different view.
[1] All of this off of the top of my head. I will not at this time be providing references, nor is this a documentary. People who want to know more are welcomed to go find out.