Position is better than Empire but remains rather difficult, once you get your hands on rebel settlements expect to get attacked by all surrounding nations. I currently have nine wars (most are inactive but i dont get any trade) due to domino effect of diplomacy. All started because of Metz, Empire didnt enjoy my intervention and attacked right away. Funny thing is Metz rebelled against their army, and the full stack keeps containing them. Apart from that most south factions will have a hard time containing feudal and templar knights often leading to giant manslaughter. Danes are the toughest i ran into i think but only had one siege so far (buggy as always so im not sure its relevant).
Oh and my advice on first thing to build : churches !