What is personality except a set of cognitive biases? The narratives we use to inform our perceptions, influence the priority of memories/associations, and inspire future decisions are as much our own making as they aren't. If there is friction between views of personality because one group prefers to look at innateness and another looks at influences - and intelligence doesn't seem to determine which group you're in - what other indicator of personality differences do you really need? For me it plugs into that external/internal locus of control stuff, messy as some of the research/conceptions of it are.
I'm of the opinion that most views we think we hold 'philosophically' are, well, personality tendencies expressed formally.
It all gets a lot easier to conceive if one doesn't assume there is such a thing as a unified self, just a bunch of modules our self-describing narrative inhabits depending on what the environment asks for at the time. Specifically 'training your pre-frontal cortex' seems easier to me than 'becoming a more organised person'. Sorry if that seems a little rambly/obscure.
