You're pretty close to replicating the Trek 520s drivetrain there. You shouldn't need the shiftmate.
I was looking at this a bit and it seems to get MTB crankset and gearing with brifters you need to stick in the 9 speed world. The right shiftmate might allow a 10 speed arrangement to work but the companies offer 10 speed only seem interested in going for bar-end shifters.
The 520 uses a Sora front derailleur rather than a MTB derailleur but maybe the MTB derailleur is fine there.