infact short travel 4x bike kinda close the one bike you really need.
100mm-ish travel at the rear, maybe upto 130mm fork and its all you'll really need.
I built a bike like this but still end up horsing a long travel bike around :s
I always suspected an Transition Triple (or similar slope bike) with a dropper added would be an unbelievable real world all rounder for most riding...
4X