You can do this, but you need to think about drainage. If there are no holes in the ceramic pots, you'll need something like broken crocks in the bottom to create a space for any excess water. Also, the plants will lose more water, as ceramic pots are porous.
And be aware that once they're directly planted in the ceramic pots, they'll be more difficult and heavy to move around, as you can't remove the inner pot + plant.
I am not so sure about the compost, but I would guess that a mix sold for pots and hanging baskets would be best. It may depend on the requirements of those particular plants. Me, I'd just use mulit-purpose if I had some to hand.
