Lovely paint job!
I would not use too much purple in ordner not to distract from the awesome frame! In addition, the build could become to "nervous". But try it out. I would prefer it without purple stuff except for some Details such aus skewers or a H20.
Have you got a DX Gruppo in mint/NOS sorted? As "DX" is contained in the name of the model you shouldn't use anything else.
I don't really like the function of the push-push Rapidfire shifters. If you do use them, make sure to take the ST-M071 (2-finger version). 4finger levers look awkward... I would take thumbshifters or ST-M075 Rapidfire Plus (not period correct, but nice in terms of function; more or less the same as XTR ST-M900, only 7speed).
Just out of interest: have you weighed fork and frames?