[ViktorV]

In high level play you have to manage your land, the hard thing is how to find the optimal route to collect your army: It's advisable to take around 15-18 turns to collect your army from an area and attack in the remaining 10-7 turns, so you can attack before the enemy numbers increase. In high level 1v1 play what matters most is the area you have, if you can get +1 area per 25 rounds from your enemy you'll probably win.

But! As both of you collect more and more area it gets really time consuming and after a point you just can't collect your army optimally. I'd argue that the biggest difference between skill levels at the highest levels is how efficient the collecting is. At that point you'll need cities. Always look for the opponent's counter to know how many cities your opponent has.

Not that it matters but I was a top 5 1v1 player quite a while ago.