… I really really love my profile as it is, but need to hear it clearly at rehearsal standing close to a hard hitting metal drummer, and as a monitor (cab) live. ...
You can't express your desire in a better way. The question remains how to achieve that.
1. You want to hear what would be recorded or what the audience would hear through PA? Go for IEM or PA (FRFR) monitors! That's the closest you can get to your "profile as is". And there's a lot of options for VERY loud monitoring. You might have to get used to it because you've been used to hear the guitar cab's direct (un-mic'ed) sound.
2. You insist on using your Marshall guitar cab? Fine! If you like it, use it. But forget about accurate monitoring of your "profile as is" ... in case you're using rigs that are based on cabinets other than your Marshall cab. For example, if you plan to use a Fender Deluxe or a Vox AC30 rig, you're stuck. Your Marshall cab can't give you the feel of a Fender Deluxe or a Vox AC30 combo, no matter how hard you try.
Most people (including me) who suggest FRFR monitoring enjoy the full range of amp/cab combinations the Profiler can reproduce. We don't want to limit ourselves to many amps with just one cab. It's your decision which direction is yours. If you're sure you want to stick with your cab, then at least make sure you don't introduce yet another stage of coloring your profile's sound.