there is no way to predict which SN will get the next transaction as it is based on human behavior
Ahem. You need to prove mathematically and holistically that is a random process and not subject to game theory. That is essentially the fundamental problem with PoS, its entropy is bounded unlike PoW where the entropy is external.
*sigh* please, for once, just read it for what it is and accept the general concept of what I am explaining.
In normal operating conditions it is random. I am fully aware that this will not always be the case, but every time I try to explain something clearly, someone jumps in and complicates it. If I was to explain something taking into account all the attack vectors, 99% of people wouldn't understand it.
Which do you want?