I'm bad at describing things but I'm going to do my best here.

I used to play a game called Planetside, perhaps some of you have heard of it. It features capture and hold gameplay primarily like we see in Warfare (the details are different, but the overall objectives are very much similiar).

A few weeks after the game's release, they introduced what they called Lattice Links... this means that in order to capture one base, you had to currently hold a base that was adjacent to it in the link. This helped to focus combat and make it more strategic instead of just a zerg fest to every possible base you could get your hands on. While it may not be seen as being more realistic by any means, it made a huge and positive increase in the level of combat between bases as there would be a push between two bases as one army attempted to reach it.

Picture: http://planetside.station.sony.com/i...manual/map.jpg
The colored circles are the bases, color designate which of the 3 armies own it. The links between them show the route in which the bases must be taken. A yellow link is contested between your army and another, grey is a contested link between two other armies, and a red/blue/purple link is a solid link between two of that army's bases.

The Lattice Link had many forks where by taking one base you could reach 2 more bases. This presented some options for each army's commander. While this effectively funneled the overall strategy of the game to a certain point, I felt it made the general combat of the game MUCH more interesting as people fought over not just cities, but strategic geographic locations that made it easier to defend bases or assault bases from.

So, a suggestion would be to add such links, obviously leaving the ability to disable them up to the players/server admins upon the mission load.