The popular vote will likely go to the latest releases of any derivation (lmde, lxde, Gnome or kde), unless there are too many user problems with installs or updates
--was happening with the initial release of the 13x versions..
Gnome (main edition) or Kde are likely to be slower, as they use more resources for a more enveloping Linux user experience !
Eye candy: personal style preferences is too much of a individual choice, however speed of boot or OS operation is more functional, so if you want performance you are better served by making a choice (your own of course and some lighter weight desktop theme (lxde, xfce, even LMDE is fast)
--but Boot speed cannot be the be-all/end-all of a user's OS experience, else what are they using the OS for: applications or clock watching ?