For $7,000 I'd get a Mac Pro for the animation and perhaps video editing and an iMac for the rest of it. You sound like you need at least two computers!
Although people have been saying this for years now, I really do think the Mac Pro line is going to receive a very significant revamp sometime this year, so it might (MIGHT) be worth waiting till mid-year to see what develops.
If you can't wait, really I'm not sure what to tell you -- there's obviously not much choice beyond the Mac Pro. I'm not sure how you got it to $17K but I suspect you could save some significant money by buying the core machine from Apple and most of the rest of it from high-quality third-party dealers.
One tip you may not be aware of is that, at this particular moment in time, anything beyond 8GB of RAM is not really worth the money. The software has yet to catch up and fully utilize >8GB (certain specific apps excepted) or 64-bit space, really.
Design, video editing and photo editing can be done on any current Mac, so those aren't real concerns -- a 27" iMac would be as nice as a Mac Pro w/a 30" monitor for a fraction of the money. But as you mention animation I'd suggest waiting to see what's around the corner.