Mythic bloodline development

[Zepheri]

If I am an arcanist with the bloodline development can I take the the archimage path bloodline intensity and bloodline immunity?

[Melkiador]

You probably can, although it’s possible you don’t count as having the “bloodline class feature”. Expect table variation.

But, it wouldn’t give you the aspects of a bloodline you don’t have like bonus spells. It would only modify the powers you do have.

[Thedmstrikes]

I would caution weighing options of the bloodline development/school understanding exploits. While they can be augmented, Arcanists are not full time sorcerers or wizards so they do not benefit from the full feature, only the low level abilities as pointed out by Melkiador's second assessment above.

I further recommend the second installment of Mythic Mania from Legendary Games as it includes Arcanist (among other classes) mythic class enhancements which may be more in tune with what you plan, should your group allow 3PP expansion books.

[Dasrak]

Melkiador wrote:

You probably can, although it’s possible you don’t count as having the “bloodline class feature”.

This would be the case. You don't meet the prerequisite of having the bloodline class feature in the first place.