Most things I think should be addressed have been mentioned here; ie, higher poly-count modeling, better curves, stronger "engine" underneath with fewer crashes.
A few tweaks I'd like to see that I've been trying to keep track of in my daily workflow:
edit:DOH!
-ability to view components/materials with the thumbnail and the name of the component beneath it. I know that if you hover over it, the name pops up, but this doesn't work that well, sometimes it hangs on one of the components displaying it's name even when I move to another component and sometimes it takes a long time to show the name. just doesn't work that well.
also, ability to sort alphabetically/numerically in this list.
-ability to drag and drop the scene tabs where I want them, and to double-click on a scene tab to rename it. I know about the scene dialog box, but why go to a dialog box what could be done right in the modeling window? also, you have to sit there clicking the up and down arrows to re-order the scenes. Sometimes I have quite a few scene in my models.
-I am a big fan of the Outliner and would like to see it enhanced. Not sure exactly what those enhancements would be but it is a great tool!!
-I'd also like to see the "Flip Along" command change with the axes of the component. As it is, it stays with the global axes.
- don't see a need for a renderer, there are some great ones out there that work well with SKP!
These are just a few, I'm sure there are more.