1. Yes to reverse footage, you use the same speed duration function, but just click the radio box that says reverse speed. that will flip the footage.
2. The same thing applies making speed increase and decrease. You use a time remapping function, and apply the changes using keyframes, to adjust the footage up and down as you want. You may need to watch a tutorial on the basics of keyframes to get that. But keyframes unlock all the power of premiere and are relatively easy.
3. Its best to use audition, Just right click on the clip in your timeline, and click edit in audition. It will auto move it to it, then just save in audition and your changes auto appear in premiere footage. Every tool has its uses. I will use premiere for video, audio in audition, unless as you mentioned I am just adjusting volume levels.
4. I personally don't use that for color changes, however I know there are many templates and things at creativecow the website. Not to mention many great tutorials on ways to create your own.
Hope this helped.
Arcanum