Haha thank god you're not playing the lannisters. The problem is the lannisters can take the riverlands losing like 5% of their forces (especially with night attacks and cpu sims) It is also a huge disadvantage for all factions. They are already the richest and taking all those settlements doubles their money. Then they can build armies in every city. All this happens in the first couple of turns. Tyrells can't even make it up to lannister territory before this happens to force them to move any troops south. They can just mass produce armies after they raid the riverlands.
My suggestion was 1 turn no siege of riverrun and raventree. 1 turn won't destroy their chances. Lannister can reach saltpans in 1 turn and maidenpool in 2. Tullys have no chance in defending that. I think it opens more strategy as Tully's might want to destroy all buildings and pack in riverrun and the lannisters have some decisions like send jaimie to weaken edmure (no chance edmure wins) or siege pinkmaiden and wait for tywin to siege rivverrun.















