I will submit a map called LOTR Big Map also known as LOTRhanni... which will be up soon. But anyways this is a good example of how you play this map but that is up to you where u attack and so forth...
mainly the baddies attack lorien because they can cut off all the southeastern goodie troops from grouping with their allies north or south.
it is a good tactic if u can eliminate 1/3 of their force in such a way :)
so the goodies try to take moria as fast as possible to connect their forces and hold lorien so that they cut off grey fom red/green
thats basically how it goes down.. its up to you tho. just have fun with it if you do play it.