Hey, Guy! I've used about all the methods you mentioned to propagate Kalanchoe cuttings. LOL I really didn't see a lot of difference. But I will say -- please don't use any sand. It tends to compress around the roots and hold too much water. Just not worth the risk. I assume you are in SF Bay area (and not Tampa Bay - yeah, I'm a little snot sometimes) so you won't have to worry about excess moisture blowing in during the summer months. So a potting mix of 50/50 perlite and soil will probably work well for you. I get a lot of rain, so I tend to use an inorganic gritty mix of perlite, turface and granite grit. I can't get pumice here, but you can in CA and it is great. Since these mixes are dry, when I put my cuttings into it I don't wait more than a few hours for the stem to callus. Sometimes I will dip the stem into powder rooting hormone right away and pot it up a little later. As long as I don't water right away I don't worry about rot. After a week I may water a little if the cutting is starting to look dry, but if there are no roots the plant can't take up the water. Some people mist when the plant is dry. When you see new growth, start watering as usual. Here's my original plant with a couple of (etiolated) cuttings started - And like yours, I ended up with woody stems - So I did the cuttings and saved what I could. And they still bloomed! And eventually they grow up - and will probably be woody again soon! LOL Don't ask me why my plants are droopy - like a hanging plant! They always do that and I can't figure out why. I have them outside in partial sun. They fried in full sun for me. But they keep growing and blooming, so I'm happy!

Those look like Sempervivums, aka hens and chicks. They are extremely hardy (zone 3 at least) and should be grown outside and where they have room for the offsets (the chicks) to spread and root, creating a colony. They will also develop their proper coloring if exposed to some direct sunlight. There are several thousand named forms with a wide range of coloring. And all they need to thrive outside is well drained soil....a popular filler for rock walls but they will grow happily just about anywhere.

Looks like Alpenglow Graptosedum. Mine are red.

I only see one. Echeveria “Perle Von Nuneberg”