Yep, GEM = Gods&Kings Enhanced Mod, as opposed to VEM (Vanilla..) and I assume/hope/wish/pray/sacrifice goats for BEM = Brave New World Enhanced Mod.
Forum and
Site. Though the mod at its version isn't polished nor entirely finished, but hey, that happens...
I do agre on the discussion regarding random elements, though I might add that there's another dimension, the

phenomena. Is it fun when a Volcano wipes out your city? Sure, you will settle there knowing the risks, but you can't resist those + 1

tiles anyways. But you will ragequit when it destroys your advancenment on the wonder one turn before you finish it! Wouldn't you?
So make the negative stuff more minor. But then what's the point?
I'd say lose the negative thing or at least make it avoidable by investing

or something else. Now you can bite yourself that you bought that additional worker instead of keeping the

for harder times...