Nice collection you chose. A well draining gritty mix would be your best bet for soil, and watch your watering succ's. prefer drier conditions, moist soil will cause them to rot. Others will give you more advice. My favorite is the Hen & Chick. Good Luck, Christine Forgot to add, 2nd photo center is the Hen & Chick...

Yes to change soil. Yes to separate. 1. spotted leaves - polka dot plant 2. sedum reflexum; not quite sure about round -leaved one, one of the sedums too 3. not aeonium - not sure of correct id 4. Echeveria 'Black Prince' 5. another sedum reflexum? 6. and one more groundcover sedum... 7. Senecio mandraliscae - blue chalk sticks?

you have some echeverias and a little jade plant (#4). they like bright light and only direct morning sun. Jade plants grow best at room temperature (65 to 75°F), but prefer slightly cooler temperatures at night and in the winter (55°F). Keep soil moist but not wet during active growth in the spring and summer. Allow soil to dry between waterings in the winter. Avoid splashing water on the leaves while watering. If shedding or brown spots occur on the leaves, it is an indication that the plant needs more water. Jade plants may be fertilized three to four times a year with a standard liquid houseplant fertilizer. During the winter months, move the plants away from cold windowpanes and out of drafts. Jade plants do not mind being root-bound. If the plant gets top-heavy and you need to move to a larger pot, transplant when new growth starts. Let the soil dry before repotting and wait four months before fertilizing any repotted plants. these aren't like cactus who can take full summer sun. put them in a west or south window, or outside anywhere where they get natural sunlight, some shade is ok. They can take a little extra water but don't keep them damp or saturated. repot w/a succulent potting mix if replanting them. the soil drains quickly. Frost will kill them, so bring them inside if the night temps drop to freezing. if the soil feels dry, water them well. do lot them sit in drained water. let the soil dry out before watering again. these are some of mine. I started with tiny clippings from my neighbors yard. look at how they've taken over the beds! and yes, they will flower when happy (the ones by the lizard). the others on the right are aeonium, also known as 'hens and chicks'.

Also compare #1 to C. pellucida. Generally, red edges on Crassulaceae family members is a product of significant direct sun. #3 does look like Angelina (Sedum reflexum / rupestre.)