Forward wells
Call this a crazy idea - I the believe the formal name is "circular file", but I want to get it out of my head.
Replace the camp gem piles with a build site for a forward healing/spawn well. It's not an expansion in the sense that it offers positive economic feedback, but it would create a more tangible reflection of map control and help move players towards the front. An advantaged team would start to run out of camps to raid and have to focus on closing out the game, while the disadvantaged team would have structure targets closer to home to try and earn an advantage. It remains to be seen if this would be a larger oscillation problem than trading camps, but it doesn't directly impact the ability to win titans or enter the enemy home area.