Can you VMC into the same class you're taking as a primary class to 'focus on your class' at the expense of feats and gain increased benefit or uses from class features, or to be able to choose from two options of a class ability you would otherwise have to make choices against?
The example in mind is a Wizard VMC Wizard. At the expense of some feats you can choose a school as your main wizard, and specialize in a different school on the VMC 'side'. Likewise you could choose an arcane bond with your primary levels, and then pick up a familiar at level three. The arcane school powers you get from the VMC side are slower than you're primary, but this would (in theory) allow you to double dip on some class abilities.
Many VMC combinations like this are somewhat useless, such as a Ranger VMC Ranger would gain nothing they don't already have and things which don't really stack (except, maybe, having more favored enemies.) But a Paladin could have more lay on hand and smite uses per day.
The Character Advancement rules don't expressly prohibit it. They do prohibit taking levels in your VMC class, but only in the context of blending normal multiclass with VMC; avoiding builds like Fighter VMC Cleric 3 / Cleric 2.
Conversely, there is no way to take the 1st level in a class twice. You cannot be a Sorcerer 1 / Sorcerer 1 and choose two different bloodlines. Curious if there was any rule or guiding principle I'm unaware of giving a hard line on if this is a legitimate option or not.