Interesting. Yes, I remember Buzen: defender plateau on the back edge of the map. As the attacker looks at it, the plateau extends to the map edge on the right, and just left of center on the left, with a patch of trees on that end. Behind the trees is a rise just before the back edge. That was one map my 47 buddies and I played on often back in the day. It is difficult to win attacking against skilled defenders, but it can be done. We usually used it when we had two experienced players and two intermediate players, and gave the intermediate players the plateau.

Very tight coordination on the part of a 2v2 attacking is essential--if you get stuck for long in the valley, the defending ranged units will shoot you to pieces. We would usually move to center together, delaying giving away which side we were going to hit as long as possible (until we were just out of range of the enemy ranged units), and then rapidly flank to the attacker right. It was crucial to get up on the rise fast. Going the other way worked too, but the rise is steeper on the attacker left, and the trees can be problematic. Going that way, if you can draw out the ranged units, drive them back (or hit them if you're lucky with cav), and get your attacking shock troops into the trees, then you have a fighting chance as long as you stay together and keep your army tight. If you try to take a shootout approach when attacking Buzen, you almost always lose.

For that map I took less ranged, more shock (at least 4 Nods) and YS (maybe NI if using 1.03), and a few cav (NC and HC). CA get shot up on that one when attacking, and NI are too slow, fatigue, and usually run before earning their cost in 1.02. I remember mixing in a Kensai or ninja unit now and then, and if they made it into the trees they really went to town. The defenders sometimes hid them in the tress too, which could be a real problem for the attackers.

That map would be very difficult to win attacking in a 1v1, I would think.