This actually is pretty easy: you just nee to set up starting res as high.Heavily in favour of some sort of this. Maybe even start with a bit higher resources. You would stil have to scout the map, decide your strat/build and everything the dark age fetischists love, while it taking up only half the time.
I don't like it though, dark age is a core part of the game and sets up everything, you cannot just skip it
Another thing:
Move palisade walls to feudal and Stone walls to castle age. This would make room for more aggressive, army focused play wihtout being too drastic of a change.
this +1000000000000