Adding to my own list: Hebe pimeleoides- blackish stems with small greyish/bluish/silverish leaves that creeps along the ground at about 1 foot tall. Excellent for textural contrast and unique appeal, best against large rocks and contrasting foliage of other plants. Hebe "McKean"- dwarf 1 foot tall and wide dome of bright green/yellow scaly leaves, similar in appearance to a common heather plant (although in my opinion much more exciting and beautiful). Excellent near large rocks and contrasting foliage and colors. Most Hebes like very well drained soil with moderate moisture. See link for more info Cotula hispidula- feathery fluffy soft grey/silver foliage, low creeping, with interesting yellow button-like flowers on thin stems. Likes good drainage, full to part sun, and moderate moisture. Excellent between rocks, with gravel mulch under plant crown and stems to keep the feathery leaves clean and reduce chance of rot. Here is a link that might be useful: Hebe Society

Hi, The tall variegated one is Sedum lineare 'Variegatum'. I've seen the golden one many times, but don't know the name. Remy

Hi, I have been very sucessful with sedums I love my sedums in my rock garden I don't have photos to show (maybe later) but google sedums and make sure you are in "images' you'll find lots

You don't say how large the area is so some of the plants I'll suggest to you might be too big for it. First things first though. Put in the rocks. The bigger the better so you can sit on them if you like. Consider running a dry stream bed from the rock garden to somewhere else in the landscape. Perhaps even to the canal. Now some plants... Aloes and Agaves are drought and salt tolerant, however they need the sun. Bromeliads are an excellent choice - a mix of Neoregelias that flower in the cup and require no maintenance, and large bloomers that do. If you want blue - try to find some "Blue Tango" for the garden, you won't be disappointed when they finally pop. Ferns will take the shade and many can stand some salt spray as well. They look great growing out of the crevases in the rocks. The one blue flowering plant I'll recommend, and it's going to need the sunniest part of the garden, is Blue Daze. You should be able to find some at HD or Lowes.