I did put 3 of these in the ground in the park by our old house, where they still persist, as far as I know, on rainfall alone. No critters have nibbled that I'm aware of, the leaves are pokey enough to make that sort of thing very unpleasant for them. They do look scrappy without regular care (and we have a 5-8 month summer drought most years) but they hang on.
Yes, it is ideal to secure the pot with wire before it is gobbled up. I guess you could run some under the very bottom if there isn't a lip. I used a galvanized wire sheathed in plastic, rated for weight (found at a local Home Depot) because the metal would likely rust out in short order otherwise, given regular watering.
I think the stems of the plant will provide plenty of support down the road as it cascades over the edge, and you could conceivably rely on that to hold up the weight of the plant later.
The key there would be to distribute the weight over many stems (a full circle around the top) to reduce the stress on any single one. You will see as the plant grows that the stems are really strong and tenacious. It is a serious challenge to extract cuttings from an older plant without the use of a sharp tool, combined with some boldness.
