Charging a 1.2 V, 1000 mAh, Ni-MH battery
0.44A isn't that low.  1C for your cell is 1000mA, so a good trickle charge rate is 0.1C, or 100mA.  It will take about 12 hours to charge.

you could charge faster, perhaps 0.2C, 200mA, provided you don't let the cell overcharge.

The voltage must be higher than 1.2V or the cell will never charge properly.  The charger must be current limited to avoid frying the cell.

You can charge at higher currents, provided you shut off the charge, or switch to a trickle charge, once the cell is full.  To do that properly requires a knowledge of the characteristics of NiMH cells.  It's more complicated than just using a simple voltage/current supply.