Will i be able to take a peace treaty .. after attacking noble troops?
There is no such thing as a peace treaty as of yet. The negative relationship will slowly decay when you dont attack any troops of that faction for a while. So its possible to get back to normal allthough it will take a while.
Apart from that there are events which can increase or decrease the relationship with certain noble houses.
Regarding the ingame lore, I think the nobles will mark you as outlaws and put a bounty on your head. I imagine it beeing pretty difficult to getting back to normal relations with a proud and infuriated noble in those days.
I think we need some kind of noble armor (with the faction’s colors ) as a reward for quests of this faction.
Like with many things the reason we dont have this ingame is, that we dont have time to paint and implement these items. Sounds sad, but that’s the way it is :)