Larger single zone infloor HW control

Chuck_17

For a single zone system (one room about 2,000 SF) does it make sense to use a primary/secondary low loss header and basically just control the water temperature at the header as required for the room?
Just thinking this through:
No control or mixing valves.
Water temperature at header based on outside air temperature. (high limit to limit floor temperature)
Secondary pump to manifold (infloor) runs based on thermostat.

Or should infloor pump run continuosly with valve to control temperature in the floor?
Low limit for condensing boiler?

What do you think?