I'm sure the answer, as with many classes, is "slight to none." Paizo really punishes one for multiclassing. Please indulge me, this is my first post here.
I'm making my first magus, and I'm after the classic Shocking Grasp-centered gish, with a bit more utility hopefully. I'm looking at a half-elf strength-based build (probably with the bladebound archetype), and adding in a level of cross-blooded sorcerer (orc and draconic) for +2 per die damage to SG.
If I can, also thinking of sneaking in a level (possibly 2?) of the Stargazer prestige class for a hex and a familiar, and for the Stargazer sidereal arcana.
My question is, an I trading away too much to get these abilities? For example, Bladebound takes away the familiar I would get with Stargazer.