I used a GT10 for many years before switching to the GT16. The most significant reason that I switched was that I wanted to use the GT controller in my studio for transport control and stuff.
The GT10 is a great choice for a controller. I use an AxeFX III in my live rig. Here is the basic workflow that I uses live:
* Presets are shown in banks of eight, with two buttons reserved for bank up / down. The up button has a hold function that goes back to the slot where my "starting" preset is located. The down button has a hold function that mutes output. This is super handy if you need to switch guitars, or during breaks.
* Selecting a preset switches the GT10 to a page that shows scenes 1-8. One of the remaining switches is reserved for tap tempo, with the hold function assigned to the tuner. The other switch is goes back to the presets, with the hold function going to the IA page.
* The IA page is generally arranged the same for all presets. I put effects in the same place on the GT, so I always know where to go for my distortion or phaser or whatever. Each of the buttons has a hold function that cycles through the A/B/C/D channels for AxeFX blocks (this is a construct of the AxeFX design). Again, I reserve two buttons for the tap tempo / tuner, and the other goes back to the scenes, with its hold function set to the next IA page. The IA pages loop back to the first page on repeat presses, so I can pretty easily scroll through whatever I need.
In set list mode, the only difference is that the up/down buttons on the main page cycle through the songs on the list.
In a bigger setup with more devices, you could be sending individual commands to each device on every button press. That's what I do in my studio, where I use the GT16 as an automation interface for the computers, DAW, monitors, synths, etc.