Front derailleurs have different cable pull for road and mountain. A MTB FD will not work with SRAM road shifters. If you go to a smaller MTB crank, try your road FD and see if you get adequate shifting.

I was the opposite. Flat bar SRAM shifters, road crank, tried to get MTB FD to work and couldn't. But that was because curvature was too tight on the FD. You may be fine with road FD to MTB crank.