In a partial profile CBC all attributes appear with one another, without respect to area, as you have here. So in this case you're not looking at a partial profile model in so much as a separate CBC for each area. So if you have 10 areas, this is 10 separate, if smaller, CBC experiments.
You still won't be able to get by with just 2 tasks per area unless your sample sizes are huge, so what I would recommend is to have each respondent receive CBC questions for 3 of the 10 areas perhaps. Decisions about adequate sample size depend a lot on the number of attributes and levels you have; if the numbers are reasonable you can usually get by with 200 respondents, so if each respondent sees 3 areas (and a dozen CBC questions per area, this means you'd need over 600 respondents.
For your last point, because this is essentially 10 separate CBC tasks, there's no need to put in a lot of constraints and try to program this as one large experiment - that would needlessly complicate things.