remember that I am not looking for a ralley cross set up. I am looking for a good general set-up that I can also take down the fire service roads and light duty off-road driving. I want a good set-up that travels well on the highway and surface streets, but can handle the dirt roads too.
There is no need to raise your front ride height if you don't need performance for dirt roads. The stock ride height is fine. On a service/dirt road you're just moving on, there's no consideration for going fast, so just go slower and you're fine.
Avoid very soft snow tires. They have very weak sidewalls and could debead or get wedged with rocks and dirt more easily.
Why would i want to relocate the weight to the rear of the car?
If you think the Focus has trouble rotating on loose surfaces, you just need to experience it to believe it.
The Focus has a decently strong oil pan in front, so it won't puncture like most. You don't have to get a front skidplate if you don't want.
When you buy your coilovers, you want to make sure that you can raise them up and still not be at the extreme of the shocks' working range. Raise the stock ZX3 ride height by about an inch. Having the engine (and the weight bias of the car) higher off the ground will give you better modulation in weight transfer. What that means is, when you get on the brakes, you'll have more control over how much the rear end slips, and thus how much rotation you're inducing.
Of course, that's all theory. Not trying to insult you, but you probably wouldn't be able to get that to work your first time out. On top of that, a lot of rallycross courses are tight for safety, where it is very hard to initiate brake-in-turn rotation. The natural reaction people have is to lift off the gas and give it more steering input, which simply won't work.