One of the things I find a shame in WvW is that each map is fixed in stone, Eternal, Borderlands, they all remain the same from match to match and the only thing that does change is ownership.
Real time strategy games have a perk in that the same maps can be played very differently. In one matchup players might build walls and towers one way but in another matchup they might build it another way. The same map can result in a very different match.
My idea of introducing RTS elements into WvW is to give more diverse battles. No more pre-determined forts/keeps and fixed locations, you begin each match with a clean sheet. Unspoiled terrain with caves, forests, mountains, oceans, you name it and it is there.
You begin at your home village aka your spawn essentially. Your spawn has a wood supply camp which gives a low but steady supply of wood to allow you to build outwards. You can build forts anywhere, any size and any layout you want. You can build a Helm’s Deep style fortress at a good location or you can build standard looking forts we have now.
Building anywhere? People would spam structures all over the place! Now here is the catch. You can build anywhere provided you can transport the materials to that location to build it. In theory, you can build a fort right outside the enemy spawn first thing but Dolyaks would take a long time to transport materials to the build site and they will be very vulnerable to attack in their long journey. The closer you decide to build the fort, the shorter the distance the Dolyak needs to travel to get wood to it.
What stops me building tons of stuff near my spawn? You can do that but think of it as building 10 trebuchets at the same time versus building one trebuchet after another. The wood supply at your spawn is steady but low so if you build many things at once then progress will be slow on all structures.
As you progress into the map, more resources open up, stone, gold and more wood. Securing stone will allow you to build stone structures and gold will allow you to hire better guards. These resources will be contested over by all three sides.
Sieging is no longer done by blueprints and supply. In order to siege a keep, you need to build the siege weapon and transport it to the location. As an example, your team might have a lumbercamp near an enemy castle that you want to siege. You would build the trebuchet in the lumbercamp and have a Dolyak pull it to the castle to deploy. Be careful though, enemies can easily kill the guard escorting the Dolyak and lead it back their their own base for use. The same applies to any Dolyak transporting wood/gold/stone, enemies can kill the guard and lead the Dolyak back to camp to take the supply or they can destroy it on the spot.
The idea behind this is to introduce logistics into the game. You choose where you want your keeps/forts. You arrange materials to be transported to the locations that need it. You arrange to have siege weapons transported to the front lines.
or might be a really bad idea :-p