Ash, definitely the 50 Lux Asph first IMO. Probably one of the best lenses, and would give you more than enough effective FL on the M8. The 50 is very easy to focus and makes for a great work horse of a lens, whether its a M8, maybe eventually a M9/10 The 75 and 90\'s are great, but a lot more unforgiving in terms of focusing and calibration.
Cory, great shots! The MFD being out, is a calibration issue, that can be adjusted. This of course is assuming your M9 is calibrated to spec also. Normally when I get my lenses back after servicing, I test for MFD, mid and far focus accuracy
The 75 and 90\'s are great, but a lot more unforgiving in terms of focusing and calibration.