Your #5 is Kalanchoe Kewensis. I am impressed that you knew it was a Kalanchoe as it is a bit out of the normal. A leaf with root very easily and when the plant gets older, it will get quite tall.
Your Aloes will be difficult to get specific IDs on as there are many hybrids. You will find they will produce suckers (more plants) very freely which is why you will find them in places like the garden centers with only a generic ID.
Agreed on the last one being an Orbea (formerly known as a Caralluma) and all in the same Asclepiadaceae family as Huernia or Stapelia.
Enjoy your succulents! Kristi