Heh, I remember you telling me to suck it up when I complained about the shitty RTW autocalc. Who's laughing now?
As for the terrain and Roman issues, they're not so tough. Here's what I've been using to hold off constantly attacking numerically superior stacks of Roman elite troops. I originally had only one of them down there in Mediolanium, then I added one to Massalia after they started attacking there as well, and finally I added the third when I took Patavium. I still only use one of them at a time, but I rotate them around for retraining purposes. Meanwhile my main armies were taking indies in France etc and are now fighting the Germans.
I fought through those same areas you're having trouble with now -- just don't fight in the forests. Fight only at cities. It's the easiest way to avoid the bullshit trees. When you DO have to fight in a forest (this should never be an important battle against a big enemy army), just put your troops in a group formation and move them around together, zoomed in. You can let them do most of the fighting on their own.
Also, get the reforms you nab. Just spam great markets, fortress temples and large cities.