I'm fine with rand(), prob(), pick(), and roll() as they currently work.
I'd just prefer that they be wrapped in an object, and the existing global rand(), prob(), pick(), and roll() procs be syntactic sugar to pull from the default random number generator.
This way we can actually instantiate multiple prngs each with their own seed so that different parts of the game can have reliable deterministic outcomes independent of one another.
Structure:
/random
proc
rand(low,high)
roll(num,sides)
prob(pct)
seed(seed)
pick()
New(seed)