Even in the summary it seems you should distinguish the SEC as a real estate development, state owned or otherwise, and as a special tariff and or tax regime. The former seems to have more room for rent seeking and inefficiency than the latter.
Not necessarily. After all, the larger the SEZ, the more costly it becomes to target particular companies with favors through SEZ status. Residential SEZs are generally quite large. That being said, if the construction business is in focus in particular, then a residential SEZ is a good vehicle.
By contrast, single-factory zones where one company in any sector is singled out as a zone, are much smaller and efficient tools for rent-seeking.