I played a bit with the simulator and came with a layout I thought out would be nice pre-launch, based of off my layout on other tanks.
Only to find out that its fundamentally different despite having the same 123 base.
After all it can go 123123124344 or whatever.

On my preference I use the "Press left trigger then right trigger to show this set left side" and "Press the right trigger then left trigger to show this set right side" setting for the controller.
While my view is always on another set thats dedicated for single target situations, or change to another thats set for AoE situations.

for a total of dancing between 3 sets.

Wish there was an easy way to share my setting...
Lemme try to explain it tho.

(Before we begin: please note that I use an xbox one controller)
So, Visually on single target Im ALWAYS on Set 3, Set 3 has all the "Long CD or requires a proc" offensive skills.
So on Set 3 Left side we have:
Up > No Mercy
Left > Bloodfest
Down > Bow Shock
Right > Blasting Zone
Y > Solid Barrel
X > Sonic Break
A > Gnashing Fang
B > Brutal Shell

Meanwhile on Set 3 Right side we have:
A > Rough Divide
B > Lightning Shot

Set 1 is the one where there are stuff I do press but don't really require my visual attention.
So by pressing Left trigger then the right trigger we have the Set 1 Left side like this:
Y > Wicked Talon
X > Continuation
A > Keen Edge
B > Savage Claw

If I happen to have a Charge that I want to dump on Burst Strike, it is on the Set 1 Right side, so pressing the Right trigger then the Left will be like:
B > Burst Strike

The logic here is that everything you need to keep track of (thats offensively oriented) will be on the left side of set 3. When you enter the Gnashing Fang combo, its a matter of pressing and releasing the right trigger to use Continuation, the other combos and see if there is any other oGCD you want to doubleweave.