There's a new option in the installer under "Flash Tools" or something that lets you use all of your flash ram. After running that (and maybe rebooting, I can't remember) you can set your partition size to the maximum.
That said, when I did that I had problems with several programs which were trying to put things in my (very small) /home partition. I think this problem can be solved with some simlinks, but I didn't really try that hard to fix it, I just reflashed to the default size and everything works great now.
The above is for a 760. I have no clue what will happen on other models.
The ideal setup would be to a maximum sized root and then create a simlink to somewhere else in your root partition as /home (I think)...then your stuff will all go to the same partition. This will eliminate problems where you have plenty of space on one partition, but the other is full. That's my plan for when 1.1.0 final comes out, since I'll probably have to reflash anyway.
The above is for a 760. I have no clue what will happen on other models. If anyone who isn't a linux noob like me has anything else to add to this discussion, I'd love to hear it.
Hope this helps!