Here's a few pics of my current Rig and the evolution from the older variax models (a maple neck 600 to a JTV 69 to go with my jtv 89).
The top picture shows what's patched into the back of my 500x which is basically:
JTV 69 into variax input
JTV 89 into guitar input
L6 link out to my dt25 which is feeding of the Left output of the POD mixer
DI out of my Right XLR straight to the desk.
I run like this for a few reasons: Firstly all my patches have their inputs set to both variax and guitar input (apart from a few special patches like a spilt acoustic/Electric dual tone) which means if a guitar dies or breaks a string I can just grab option B (usually the 89 on a guitar cable) without unplugging/plugging in guitars (which can be slow on the digital neutrik connections with the variax's). If this happens I just need to manually change models and/or tunings on my 89 as required.
All my tones are dual tones with different sounds out of left and right, although most patches share effects (for example a tube driver on fs1 which will feed both amps). I set my output to studio direct (Manually because the L6 defaults it to combo out) but run the Left side of my signal which feeds the dt25 with no cab sim and usually pre version of the amps. The right side uses full models with cab sims, and different amps to the left for a bigger stereo sound.
This combination serves a few purposes, mostly a bigger better sound due to the two different amp models panned left and right feeding front of house. It also means I always have redundancy if one of my channels goes down (Eg if the dt25 blew a tube), they always have the other side they can work in mono. The DT is also the backup if the POD dies, I just go old school 2 channel and ride the guitar volume more.
The complexities are remembering to set it to studio out manually, ensuring the FOH guys hard pans my signals, and making sure the monitor guy only sends me my Right signal though the wedge, as I get plenty of my Left channel through the DT25 on stage. I get a cool, fat front and back stereo image from this set up and a blend of my favourite amps without potential phasing issues that occur when blending models.
I'm lucky in that I mostly play big rooms (500-3000 people) with good quality PA support. I had thought about running dual DT amps but this method gives me the best of both DT setup and a FRFR speaker, which is ideal for some of the acoustic stuff I do.
I do play smaller gigs too, and take smaller rigs on fly in/fly out gigs, often just my JTV 69 and HD500x, for which I have a whole other set of patches set up to go direct to the PA. In this case where possible I ask for a stereo Foldback set up, or if that's not possible I still send stereo to FOH but only ask for one side of my signal through foldback (again to avoid phasing).
I do love my dream rig setup, I play a pretty wide variety of stuff and as a guy with a studio production background I really do enjoy being able to bring a very versatile, complex set of sounds to the gigs. It's always a balance between have solid core sounds and also setting up specials sounds for specific required tones (eg a vocoder for 'livin on a prayer', or organ sound for 'lonely boy') but that's half the fun.
If you have any questions, happy to answer them. Cheers, Ben.