My reflex is to consider edge cases.
For example, what happens if this is launched, works, and then a Krakatoa 2.0 goes off. What's the game plan in that scenario?
Sincere question, these systems are well beyond me.
Then we stop increasing albedo for a bit. Basically PWM-ing the Earth's solar flux. As long as the decay time of the albedo modification is known, it's quite unlikely that we could induce a snowball earth.
Sounds like a Hell of a risk when playing with a complex system that is not yet fully understood.
Don't worry- Russia has a vested interest in warming the earth a bit, so they'll put out CO2 to counteract the cooling.