In India, most of the Networks adapted IEC-60870-5-101 (Asynch Protocol) for quite some time. In Karnataka we have now gone for IEC-60870-5-104 (IP Protocol). How DNP-II supported equipments could be interfaced with existing SCADA working in IP Protocol? The S&C Equipments cannot have a separate distributed Architecture, as you have rightly mentioned. It has to work with an existing WAN.
Spread Spectrum Radio is still not approved in India. The B/W mentioned is also not available. Here a free Band is available for Multiple Access Relay Radios (MARR)In Karnataka, India, every thing is through VSATs only with an exception of additional OFC in Bangalore City. Hence support for other Communication Media is also should be looked into. MARR provide minimum Latency but suffers from coverage. It is good for small towns but not to an entire State.
The Indian Networks use Unix or Linux for security and not a window based System, where as IntelliTeam Remote Set Up S/W works on Windows 98 Paltform
Not much details are available on Database. We normally adapt Oracle 10G. This should not be a problem in S&C configuration