I've found getting low volume is more about the speaker cab than the amp, if I run my small amp through my 2x12 cab it's hard to get the volume under control for a quiet jam whereas I can put my 900watt head into my 1x10 and practice upstairs whilst the Mrs watches television in the room below without complaining.
The GK cab will probably stop you from getting any actual benefit from the bigger wattage head though.
A Genz Benz Streamliner head sounds ideal if you can find one, paired later with a pair of nice 1x12s will give you a great modular rig, the GK head and one cab for home practice, genz head and one cab for louder practice/rehearsals etc, genz head and both cabs for proper gigs with the GK head as a spare 😁