my thoughts. first DEFEND THE HOMELAND! Too many of us wandering to other nations ;p
Second, let the NPCs take the first hit. Beastmen seem to love mob tactics. You hit one, you aggro/link the whole damn pack of them. It really sucks. Then they roam from person to person, mowing them down. But if you let the NPCs establish some hate first, it'll be easier to pull targets off them. That leads to less player deaths, unless you get the worst of the NMs, and more freindly control.
I realize that's not exlusive, by any means. Ever since the patch, campaigns have gotten kind of nuts. Your first one or two waves comes in, and always pops up a Belfrey: AKA army generator. If you don't bash it down quickly enough, you got more waves coming. On a positive side, you don't have to jump all around to max out your XP gains, since you get a good helping of battle in one spot, with no waiting. On the negative side, all the extra carnage has done some major damage to the allied standings (I believe ONE non-city zone controlled by the allies this week!).
This requires a lot of cooperation, among campaigners. For example, in Windurst, they've done well to retake control of the city poper, but now that they have the foothold, we really need to start pushing back out. Start small steps, by pushing forces out to Saruta-Baruta, and go from there. Once we retake that zone, push onward to Fort K-N, etc. I don't believe the beastmen can attack a city if you control the neighboring zone. That may have changed also, but who knows. Just like with any major change, it'll take a bit for the players to adapt. Give it a few weeks, though ,and we'll be bashing beasties, just like old times.