I agree.
2) Make sure new iMacs are preloaded with MacOS X 10.5.2.
They will as soon as the OSX.5.1 versions already in the pipeline are sold out the spigot. If you buy your iMac at a Apple Store, they will upgrade it for you for free.
3) Provide a better keyboard (the current iMac keyboard doesn't look like it's comfortable for long-term typing).
I disagree. I bought one of the new keyboards for my G5 Tower and it is wonderful to type on. It is very comfortable and easy to use.
As one used to the Microsoft Natural Elite keyboard, going to the new Mac keyboard was an uncomfortable experience—it felt “unnatural” (literally!) and the typing feel wasn’t that great, either. You can use the Microsoft Natural Ergonomic Keyboard 4000 on a Mac, but I’m hoping Microsoft offers a version with extra function keys designed for MacOS X 10.4.x and 10.5.x versions.