Maybe I've overseen the setting but I think it would be great to actually mixing the already existing cabinets. So one cab is the standard 4x12 and the other one is let's say the Mesa Cab. With a volume slider and a adjustable delay there would be more possibilities to get some interesting cab sounds.
I know this approach from VST IR Loader like NadIR or LeCab where someone can load two impulse responses, adjusting high- and lowpass filter, volume and the delay IR's. It is possible to emulating 2 mics.
Did someone considered this already? Or is there a Linux plugin that makes this possible? I also ask because I like the integrated cabinets from Guitarix and would like the opportunity to mix two cabs.