So i need to decide who to side with. Since im such a huge fan of Skellige, ima base my answer around them. In the quest, Reasons of State. who should i side with, Roche and Ves or Djikstra? Which one benefits Skellige more?

If memory serves, I don't think that particular decision has any noticeable impact on Skellige (if at all). Skellige's future is determined by another decision you'll have to make further in the story. Not sure if that answers your question, but hope it helps.

I don't think it impacts Skellige but it does affect Temeria and Redania.

Its more fun to guess and see.

It depends what you want. You can either have peace for Skellige, war, or it just fall apart or something like that if I remember right.



*SPOILER*
Now choosing between Djikstra or Roche and Ves, decides who wins the war between Nilfgaard and Redania. If Redania wins (and you choose not to assasinate Radovid) then I think he would invade Skellige afterwards. I ended up choosing Ves and Roche and Nilfgaard ended up winning.
*SPOILER*