Locking chocks will help reduce the rolling of the tires. There are two main versions, the X-chock which you tighten between the tires and the Onestep chock which places opposing chocks on the ground between the tires.
I prefer the Onestep, because its an actual chock and prevents rolling. The X-chock isn't really a tire chock, you still need to block your tires. I think they both work reasonably well, its just personal preference.
The next thing that you can add on is the JT's Strongarm system (not sure if there are other brands of this or not). They are triangular braces that attach to your frame and then come down to your stab jack and help reduce the motion that way. I haven't used these, but I've heard lots of good things about them.
If you find you get a lot of up and down movement from your suspension, perhaps adding another set of jacks just ahead of your axle will help with that.
The last suggestion is just to walk more gently. My kids and wife like to stomp when they walk. You can clearly feel more shaking and swaying when they walk. I've got friends that are heavier but walk more gently and the motion is quite reduced just from that.