Not an expert, but I believe many papers on other video games make a single decision for the next X frames at once, possibly including a delay factor that governs exactly when to act. I think OpenAI’s Dota2 agent does this.
From what I understand, the OpenAI Dota 2 AI has a long-term strategy module which was mostly trained by imitating 60,000+ replays played by human professional teams. My problem with doing that for the Borderland competition is that I don't have any data source for replays of someone playing the game really well. You control 3 units simultaneously and it's 2 teams against each other, so I'd need 6 dedicated volunteers playing the game for many hours to create a reasonably-sized corpus of human replays. And who says that those people are good at it?