That list seems like a solid start, though I agree with Draziya: it would potentially benefit to include more about the character's inner life (if you haven't already), as that's the true guts of what makes a character live and breathe on the page. Instead of a list, try thinking of it as a questionnaire-- it might help to address your potential characters the same way an actor prepares for a role, or as you would break down a book in a literature class or reading group. Whether you actually explore all the specific questions listed below or not (and I often don't!), being *able* to answer them can prove a good barometer for how fleshed out a character is.
Not everything necessarily belongs in the story (an iceberg approach is solid: not everything should be on the surface), and you probably don't need the whole life story of Jimmy One Scene mapped out-- but I find this sort of approach can help "see" (and write!) elusive characters more clearly:
- What does the character want during the course of the story? What do they want from their lives beyond the confines of the immediate plot?
- What prevents them from getting what they want?
- What are their strengths? What are their weaknesses and flaws?
- What experiences have informed their worldview?
- What is their default mood / state of mind? (calm? anxious? irritable?)
- How would you characterize their intelligence? How do they speak and present themselves?
- What other relationships do they have?
- How do they feel about the other characters?
- How do they feel about themselves? What internal contradictions do they have, if any?
- What stands out about them? What does their voice sound like? How do they walk?
The primary goal, in my approach, is to bring the character enough into focus that you can have a conversation with them, as an entity separate from yourself (this is also helpful in establishing the character's individual voice). Everyone is the protagonist of their own story in life: what would that character's story be, if you were to tell it instead? This peripheral knowledge, used judiciously, can even help propel the story you are
All this said, in my personal process (not intended as a measure of the 'right' way to do things, just my own), I don't usually start
with a written character sheet, because then I sometimes feel 'stuck' with whatever I wrote. Instead, after deciding who belongs in the story I want to tell (sometimes there's a logical inherent population, other times I pick specific traits or types I want to experiment with), I try those yet-unformed characters on the framework I'm creating. I ask the above questions internally, just to get a feel for the characters-- flaws first for allies, positive traits for antagonists, because it makes them human. Then I start writing, because often once I put the characters and plot in motion, different, more exciting paths open up, or a character I didn't plan waltzes in and bumps out a different half-baked personality. Only after the characters prove they're going to stick around do I create an actual written sheet for character profiles and continuity (useful, so I don't forget key things... like that a character has glasses, or makes reference to a brother in one scene, or hails from a specific location, etc).
I hope this helps. Happy writing!