You're using numbers that plain don't matter, that's your mistake. Your math is way overcomplicated.
For one, all of the non-damage effects of crit can be converted to a damage gain and averaged. As ichime has noted, 31.5% is 5% more than 30%, so the total damage gain from increased crit can simply be calculated as a 5% increase to this gain plus the gain from simply doing more critical damage.
The absolute lower boundary for the gain from 1.5% crit at this point is 1.2%. I don't know what the average gain from additional dot ticks and SS procs is(and really don't care enough to calculate it right now), but we can guarantee that it is >=0.
At no point during all this do you ever have to calculate the number of actual critical events. It's completely irrelevant.