this may or may not be useful but i've had good happenings with a marshallized valve junior head with a bitmo simple L-Pad attentuator. of course, i use a modded CS-3, BD-2, and SD-1 to get a proper metal tone at low volume, but the valves do their bidding. the CS-3 prevents loud clean peaks for going too loud, and give a good volume boost. the BD-2 is there for tone coloring. a cheap EQ i guess, and the SD-1 provides the bite when i need it. but the attenuator makes the whole thing usable at appartment volumes.
but, unless you want to work on your soldering skills, keep the cube. maybe get a trade-in for a cube-30x with that power squeezer. it's the same amp, with an onboard fixed attenuator, can be good especially for practice purposes.
keep in mind that if you boost something, you're gonna have to turn it down somewhere. and if you turn it down, you lose that power tube drive, making tubes useless. unless you turn down the actual signal going to the speaker, and that's an attenuator. but an attenuator can make you lose some bite to the signal, especially for bedroom uses.
