I find the XTR stuff holds a huge premium for hardly any gain over XT gear:
The XT shifter now has the same functionality (although the XTR still looks nicer);
There are better V-brakes to be had eg Pauls, or Avid; (Pauls also have nice levers)
the XTR cassette is partly titanium at high cost and they don't last longer than XT at all;
I think FSA offer nicer, lighter cranks eg their team pro carbon cranks at comparable or better price;
the xtr shifter won't work with SRAM dualdrive derailer - the pull ratio is different.
Sorry - I don't mean to confuse you or tell you I know better - just my own opinion.
And I'd like to see you get your money's worth of upgrades.