Unholy DKs with pets cheese the freeze (pets stop Frozen Storm just fine).
As a Unholy DK that currently got both cities on 4 masks and currently working on getting 5 masks run going I find Orgrimmar and Thrall much easier compared to Stormwind City and Alleria.Though I do find Shaw easier than Rexxar but the rest I find Orgrimmar easier and that is my opinion I am not going to argue if you disagree and find something differently.