Thanks for all of the answers guys, really appreciate it! I'll try and answer some of the resulting questions below
Some of the merged stuff sounds a little strange but I'm now wondering if this is an issue with the cabs at the rehearsal studio. I've just unpacked my 2x12 and will be bringing it along with me tonight to see if that resolves the issue. Another possibility is that the poweramp in the powerhead could be adding something to try and emulate a tube amp or something. I have a QSC power amp that I can try as well and see if the problem persists here.
I was previously getting unfavourable results with the direct profiles as well but will try them with my cab tonight. At the moment I'm kind of with Skyhighrocks in that overall the tone of the studio profiles seems to have more feel or magic!
Through my studio monitors at home I get a great sound and no extra bass so this is why I wanted to use these versions as this is key but I like decent sound onstage too and prefer a real guitar cab, although I've not rules anything out at this stage and FRFR is something I'm considering again with the general high quality of profiles available these days.
I don't think the profiles sound thin until I have to remove so much bass on the direct monitor out EQ to remove the woof
My monitor out has the cab disabled and it's my understanding that the monitor out is the one connected to the speaker out of the powerhead so I should be good to go with the cab maker and EQ.
I don't expect the studio profile with cab driver and a direct profile to sound the same but in general they seem to have something more about them.
Thanks again, I'm hoping that it's just the cabs to the studio so will report back after rehearsal tonight.