I've never done a gongfu on lapsang souchong, but I have with other black teas.
My usual black tea guide to myself would be 1/3-1/2 filled gaiwan, flash rinsed with boiling water, brewed once for 30 seconds, then brewed for 15-20 seconds, then 30+ sec for subsequent infusions! Usually a 120/60mL gaiwan!
It sounds about right that the smoke would mellow, the short infusions might not give it time to exert it's dominance over the flavours from the tea! Which sounds more enjoyable to be honest!
If I was to suggest anything I'd say take the scale down to under 150mL of water if you can (Do you have a gaiwan?) and experiment with that without wasting too much tea
You'll find it easiest to control at the 100mL level I think! Happy brewing!