Your "intuitive factors" are useless for public debate since different people will often intuit different answers.
Does it mean the developing child should be able to forage for its own food and own its own living? Certainly not -- infants and children are easily recognized by everyone as fully human, though they are dependent on their parents for many years.
Your premise is flawwed. Any number of cultures and prominent philosphers disagree with your premise.
As for your "intuitive factor", a pro-choice woman that I used to debate with on the Internet mentioned explaining abortion to her child who responded, naturally, "That's killing a baby." Look at the polls. People's intuition is not what you think it is.
By the way, one of my favorite questions for pro-choice people is that if you crash-landed on an island and the only survivors were you and an infant, would you be obliged to take care of the infant or could you leave it to die. You might (or might not) be surprised at the number of "no obligation" pro-choicers out there.
But caring for the infant is the job of the government, and Congress should create a multi-billion dollar program to scour deserted islands for infants who have survived plane crashes. Yeah, that's it.