Thanks everyone for the input! I appreciate the help. I ended up pulling the trigger and installing a top hat.
The parts I ended up using were the Penn-Elcom M1551 top hat with backing plate, and the Duratruss dt-3800l crank stands for the tripods. (Penn-Elcom seems to be an awesome manufacturer if you're looking for miscellaneous speaker cabinet parts, very high quality.) I used a part of another tripod to roll the speaker on, marking the balance points as people described in this thread. Then I also did a "dry run" by just balancing the speaker on the tripod once I established my center of gravity and was happy with how it felt. Once I felt very confidence with the center of gravity, used a drill bit for drilling the right sized hole ($20 at the hardware store) and then crossed my fingers as I drilled through the cabinet. As it ends up it's at least an inch of birch plywood. With the backing plate on the interior of the cabinet I was able to really crank it down, I am very happy with how sturdy it feels and the appearance is very clean as well.
Here is a picture of the first show with the new setup, I really prefer having the subs on the floor, SO glad I ended up doing this. Thanks for everyone who had input one way or the other, much appreciated!