Coral Reef Succulent Container Update

"Last time on The Rainforest Garden..." I had started a succulent container with a coral reef theme, using drought tolerant succulents that have a look resembling that of marine life.  I started out with an Aloe "Crosby's Prolific", a Stapelia cutting (also known as Starfish Flower), my cactus seedlings and a Vriesea Fosteriana.
A lot has changed since then, and I'll be phasing out the more terrestrial looking plants in favor of those that fit the theme better.

Click this link to see how it started out, in the original post back in March.

As you can see, its gotten a wee bit overgrown and in desperate need of more coral-ish plants.

Amazingly enough, the Stapelia cutting has really taken off and has begun to clamber over the edge to novel effect!  I was considering taking some cuttings to neaten it up, but I'm curious to see how it does cascading over the container.  Not only is it prolific, but I'm pretty sure I saw a tiny flower bud the other day!  The flowers of these milkweed relatives are notoriously bizarre, resembling giant starfish with psychedelic markings and emitting a smell like carrion to attract pollinating flies!  I've heard that the smell isn't so off-putting as would be expected, but we'll see.  The starfish flowers conveniently tie in with the sea life theme, and the stems have a look reminiscent of columnar coral, complete with wavy textured margins!

This... echeveria... (I think?) has gotten pretty big and it putting out a stolon that might become a flower or a plantlet.  I really have no clue, but I some of you like Julie of A Succulent Life and Evelyn of Sensational Succulents should be able to help.  And while I have your attention, maybe you can help identify these cacti!

I'm pretty sure the ones in the foreground are a type of prickly pear, but what kind?  And what about those pretty columnar ones in the middle of the arrangement?  They seem to look a lot like organ pipe cactus seedlings I've seen in pictures, but I can't be sure.  All I know is that they're almost big enough  to transfer out into the garden and replace with some more coral-ey looking succulents.  Like this one!

Isn't it ugly?  I mean, beautiful?  It's called Cereus Forbesii Monstrose and it has the look of coral like no other!  After I bought it, I realized that Julie of A Succulent life used it in her Succulent tire!  I saw a picture of this plant online that was taller than a house, but I think I'll have a while before it gets that big.  On an unrelated note, the plant in the rear is a variegated spider lily!  I finally found it at a local ace hardware tucked away behind some gingers.  Here's a better shot of it.

Since they're tolerant of both drought and flooding, it will be perfect for the part of my yard that gets flooded in tropical storms, and it will even pop out of the background like a spotlight!  Yay me!