Precision circuit that is CC and CV circuit or power supply
If you want precision, then your CC source doesn't cut it, what with transistor alpha an' all.

The classic way to do this is with two loops







simulate this circuit &ndash; Schematic created using CircuitLab

Both the voltage and the current feedback are scaled and referred to ground, and compared against your DACs, and the comparisons OR'd into the output control, suggest a darlington for convenience. Whichever loop is 'over' pulls down the collector and regulates the output. 

Note that stability needs to be maintained, ie designed for, so the comparison is done with lowish gain. If high gain is needed for precision, add an integrator in the loop. I would guess that such would have to come after the control OR, otherwise the inactive integrator would saturate and take a long time to recover when needed to take over.

With your low voltage and current requirement, a linear supply is all that's needed.