I've been doing some sims to work out the best bomb/trinket combination in bis gear for frost. I've made a little spreadsheet to show all the results here:
All the sims were done with 100k iterations and averaged a 0.02% dps error.
There's some interesting results including that frost bomb beats nether tempest on a patchwerk fight and nether tempest with LotC and EoT is the best for a helter skelter fight.
For frost I highly recommend simming your own gear to find your best trinket priority as it doesn't seem to follow any fixed order from what I've seen from simming bis gear and my own gear.