I haven't found this to be an issue. I use a (1x12 + 1x10) 4ohm cab rated at 600 watts and the amp is more than capable of keeping up. I never go through the PA unless the venue is larger than your typical pub or club, and have yet to find an occasion where this amp is lacking.
I get this. As I've said before, the amp isn't really for live work unless you are happy with spending some time tweaking the amp to get the sounds you like set up. I have settled on chorus, octave and envelope filter as my live effects, and I'm fine with that, especially with the compression and drive on tap as well.
Indeed. My amp doesn't do this!