Agreed with the above for 1).
2) is a bit problematic, did you make a typo and say "Bloodline Arcanas" when you meant "Bloodline Powers"? As your question is currently written I would have to disagree with the above responses and say the answer is no - a Bloodline Arcana is a separate feature of a Bloodline (possessed by Sorcerer Bloodlines but not Bloodrager Bloodlines) that is not mentioned in either the general Bloodline Mutations rules you have presented or the specific Blood Intensity rules. You can not trade a Bloodline Arcana for a Mutation. You can trade either a Bloodline Power or Bloodline Feat, as per the text.
My question was unclear, and I apologize for the confusion. What I was trying to ask is this: The general text of bloodline mutations mentions that I can "purchase" the individual mutations for the bloodline powers they mention OR a bloodline feat of an appropriate level. The individual mutations does not mention being "purchasable" for bloodline feats though. Does that mean the general text for bloodline mutation was incorrect or not?