How about sidux (now called aptosid)?
I played with it when I was pretty much a noob, and found it to be reasonably easy to install and manage. It's bleeding edge, it uses apt, but -- it's sid.
I'm assuming LMDE isn't bleeding edge enough for you, or I'd have recommended that. IIRC it's rolling release.
I'd give sidux/aptosid a hard look if I were you though. May have another look myself now that I think about it. :-)
>We aim to be 100% compatible with debian sid, and we are at the forefront regarding the definition of a 'rolling' distribution.
aptosid(debian based distro) xfce version. Its faster and more lightweight than xubuntu and runs on a newer kernel. It's a rolling release, so you’ll only need to install once.
aptosid Based on Debian sid, but they use their own kernel and some own packages. It's actually pretty much stable if you keep looking for upgrade warnings. I would give it a try.
I've also used aptosid (http://aptosid.com/) which is cut off of debian unstable. I've found it to be a pretty good mix of up to date and stable.
It makes building packages from git source easier since the dependencies are generally recent enough.
Keep track of Sid status. Check before you upgrade. Wait to upgrade if there's a problem -- it will get fixed.
Siduction (http://siduction.org) forums, look for Upgrade Warnings (Siduction IS Sid, with occasional fixes). Debian transitions (https://release.debian.org/transitions). The debian-user mailing list. The various Debian forums online. Aptosid forums (http://aptosid.com) are worth a check as well.