The existing map variations have something that go against them, because:
a) Classic K3K map has the no-immunity ennead which to be honest looks like an obvious bug that never got fixed to keep the quest newbie friendly.
b) Classic dunc map has very wide areas right on the start. Can't tell if that is an intentional design to allow people to do short version of the uber without requiring teleport.
Also old dunc map has this narrow entrance which is the result of tileset transitioning. I think that's possibly another advantage.
But a note, this topic isn't about upcoming map variations. It's about the existing ones and whether the concept should be dumped for most ubers due to some people re-rolling map (ureh map will be hardened eventually regardless of these poll results). There are many, many bugs to fix in the new patch and I don't think my time is best invested doing map variations which are cool but noone really look forward to.