If only I've read this kind article months ago. Mr Stein, you made very good point about 'invasive' potential of various succulent. While I live in Indonesia, we have climate somewhat similar to your place (being difference only monsoon flood instead of winter).
Seems some succulents like those you've mentioned gone rampant in this kind of climate. Even monsoon rainfall won't affect them (at least not in bad ways). Seems going half thirsty in desert climate doesn't mean it can not adapt to a more wet areas.
Kalanchoes, like you said, are the most annoying things. I should have started worry when I found a plantlet grew in a dirt attached to my boots.
Aloes, common plants in Indonesia, I've seen them taken over whole roofs if untended. In climate such as ours, they don't even need someone to water them. A colony can stay and grow for years with nothing but annual rainfall.
Drimiopsis is another annoying little bulb succulent which just won't die. Every fallen leaves can grow into new bulbs (not to mention original plant) and they aren't affected with too much water either.
Wow. I never thought of agaves as being the traveling types. I just moved into a climate where I can finally have some agaves, and I'll have to keep that in mind. Agave is NOT something I want to fool with once I've placed it in it's "forever" home. Thanks for the tip!
I'm also growing delosperma cooperi for the first time, and really loving it - but it does spread quickly after the first year. I've learned to plant it only at the base of sturdy, deep rooted plants that won't be smothered by it or pulled out with it when I am forced to thin it. It looks especially nice around the feet of yucca and agave. Of course, when you do pull it up, keep in mind that every little piece will root and start a new colony - so don't drop any!
Some succulents do surprising things. I planted a small variegated 1" tall groundcover sedum (name unknown) around the base of a low planter last year, expecting it to form a mat around the foot of the planter. This spring I was surprised to find that it had "climbed" (more or less pushed itself) up the side of the planter and taken root inside. And it was such a dainty looking little thing! Whoda thunk???