You're right, there's really no reason I keep the horse archers around after yellow is defeated. They were there until yellow resigned because after destroying the TC there's usually still a few villagers lurking around that need to be hunted down. But after that they could absolutely help with red. Probably it would take 3 or 4 minutes to get them there but it's worth it to have any extra villager-killing help for red I can get.
I also tried having some fun with Barbarossa 2, and I successfully killed all 3 of my allies with a minute to spare before 6:40, but for some reason if I set one or both of the "feeder" allies to enemy (which is nice since they don't reciprocate and set me to enemy, plus my units auto-attack them), then Poland waits an extra second until 6:41 to resign. So to have the most fun but achieve the best time I think I would have to kill both of them when set to neutral, which is much harder. Annoying. I do have a 6:40 recorded with just destroying green (Bavaria). I'm interested now to patch the game again and see if this whole thing works with the patch I've used for the rest of the game (which I suspect it will).
I also tried having some fun with Barbarossa 2, and I successfully killed all 3 of my allies with a minute to spare before 6:40, but for some reason if I set one or both of the "feeder" allies to enemy (which is nice since they don't reciprocate and set me to enemy, plus my units auto-attack them), then Poland waits an extra second until 6:41 to resign. So to have the most fun but achieve the best time I think I would have to kill both of them when set to neutral, which is much harder. Annoying. I do have a 6:40 recorded with just destroying green (Bavaria). I'm interested now to patch the game again and see if this whole thing works with the patch I've used for the rest of the game (which I suspect it will).