Would you, please, explain how you managed to reduce the number of hypos during sleep ? I have that problem and couldn't find a solution.
I use a Dexcom CGM with xDrip (although you can now use the Dexcom app). My low threshold is about 5.5 because sometimes when my CGM says 5, my meter says 3.5.
If you find you go low on nights after exercise, I wouldn't recommend Lantus as it takes too long for a dosage change to take effect.
Normally I use a pump and slash my basal for the first 4 hours of sleep after exercise. However, I have also found Levemir + Metformin to be OK. (Metformin helps reduce the morning liver dump so it is easier to stay stable throughout the night.)
If you have any questions feel free to PM.