Definately a difference between power and speed. Within our dojo we train with varying emphasis on power and speed, as it has so much effect on the ability to blend. Starting from the easiest to the hardest I would say that we generally do:
1. stationary attacks (to get the concept of the technique, to develop extension and centering).
2. Gentle, continuous, flowing attacks (to introduce the idea of blending).
3. Powerful attacks (to show how blending can work effectively with strong attacks).
4. Fast, powerful attacks (to develop instinctive reaction).
5. stationary attacks (to enable movement to be generated from stationary situations).
(although 1 and 5 seem similar, they are different in what is expected from nage).
These are not necessarily done in this order, it generally depends whether blending, reactions or technical aspects need improving.
Yep, we do practise defence from kicks. Although people are rarely kicked (whilst stood up), it does happen, so it's useful to have a contingency to deal with them. I think part of self-defence is just knowing what people can do to you, and not being suprised by it.