eBook Reader -- Well, you have that NOW if you want it. Just email yourself the book in your choice of txt, doc or pdf, and you can read it just fine. Would be nice to have a better interface for it, but it's not a big deal.
Sketching -- I actually wrote an AJAX app that did this, before finding out that the iPhone didn't support the necessary mouse movement events. Problem with it will be that the iPhone's screen is just wrong for drawings of any meaning or precision. My app was called "Fingerpaint" and was nothing more than a diversion, the kind of thing you could set your kids on or doodle with at the bar.
VOIP -- Really now. You want to use a cell phone to get the internet so you can make phone calls on it? Dumb! And since the biggest argument FOR would be to save money on phone calls, you can bet AT&T will resist all the way.
iTunes Store for Phone -- Would be great for podcasts and internet radio, and I bet I'd use it once in a while for other stuff. But Edge is too slow for full res video downloads.
iMovie -- What is he stoned? The technical aspects of this aren't that bad (we have hardware to create video and play back video, so all you'd be dealing with is splicing). But having worked with small devices before, I can say they are obnoxious to use for creating rich content (Word Apps, Excel Docs, etc). Mail, Events and Contacts are enough for me, thanks.
However, some Apps we really, really need:
iChat.
Internet Radio.
Flash (just necessary for too many sites).
Some that might be nice:
A dashboard.
A very basic money management app -- check your bank and credit accounts, record purchases, etc.
Movie/Audio recording (though I doubt I'd ever use this).