Just want to highlight a little snippet of information we can get from this interview: terrain pieces' footprint won't be preset and template based (like in Runewars) but really freeform. This might seem obvious for squad-based wargamers, but personally coming from Runewars, I was wondering which way they would go with terrain for Legion.

So freeform terrain associated with preset terrain keywords/mechanics; thats sounds good to me!

Curious to see how they will deal with this during organized play, but let's not jump the gun. :-)