thanks for your reply
According to some memory usage testings, MATE desktop uses about 56 Mb of memory resources, compared to 96 Mb of XFCE4. Its menus are better looking and has an easy to use menu editor.
A dozen of applet can be added to its panel, similar to XFCE's panel applet.
As a bonus, even Mint-Menu can be added as an applet, to use as a main menu.
I am not the fan of he attached packages (caja, pluma, etc....), prefer to use a lighter pacmanfm and leafpad (from LXDE)
WATTOS is a very promising distro, -- I have tried many Debian based (point Linux, seduction, crunchbang, sparky, etc...)-- and WATTOS turned out to be one of the best one.
I only tried the MATE version, and as you said, this still needs a little bit of ironing.
Keep up a good work and looking forward to try out a next release !