Since you want to suspend the ceiling, the path of least resistance would be to lay the pipes in there. Or rather, to tack them onto the filigree ceiling from below and then hide them later. The necessary openings should be determined and executed beforehand.
As Lumpi_LE has already written, many roads lead to Rome, and each has advantages and disadvantages.
Pipes in the concrete ceiling mean different statics than without.
In our case, for example, we have everything on the raw floor of the upper floor in the insulation layer for both stories. The valves simply point downwards or upwards depending on the room. But we used metal ducts.