Previously I just had all =~ 12 pounds of grain in 1 bag, no rice, mash for 60 (same) at 152F (same as now), sparge at 172F (same) and about a 15 minute sparge and that got me low 50% efficiency.
Now I mash at 152F for 60 minutes, split the grain bill into 2 bags (stacked), put 4oz of rice...